CASCACascade Atlas

Evidence dossier

CVE-2023-33009

A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through…

Exploited in the wild (CISA KEV since Jun 5, 2023). Zyxel reports CVSS 3.1 9.8. EPSS estimates 28.1% exploit likelihood as of Aug 27, 2026.

83.1–85.9Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.

State
PUBLISHED
Published
May 24, 2023
Updated
Oct 21, 2025
Evidence coverage
98%

Evidence chronology

What was known when

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  1. Source dateSource date omittedFirst observed by CASCA
    CISA-ADP

    Record text: CISA ADP Vulnrichment

    Inspect raw assertion
    Field
    container
    Value
    CISA ADP Vulnrichment
    Original evidence ↗
  2. Source dateSource date omittedFirst observed by CASCA
    CVE Program

    Record text: CVE Program Container

    Inspect raw assertion
    Field
    container
    Value
    CVE Program Container
    Original evidence ↗
  3. Source dateSource date omittedFirst observed by CASCA
    Zyxel

    Record text: A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.

    Inspect raw assertion
    Field
    container
    Value
    A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Zyxel Multiple Firewalls Buffer Overflow Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Zyxel Multiple Firewalls Buffer Overflow Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 28.14% probability · 97.96th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.281440000000; percentile 0.979630000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Jun 5, 2023 · first observed Jul 19, 2026

Exploit likelihood28.14%

FIRST EPSS · score date Aug 27, 2026 · 98th percentile · first observed Aug 27, 2026

SeverityCVSS 9.8

Zyxel · CVSS 3.1 · first observed Jul 19, 2026 · same-version scores align in this snapshot

Evidence detail

Source limits and decisions

Why each evidence state has this value

casca-unknown-reasons-v1
Exploitation statusEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
None
Affected productsSource-reported scope

The cited source assertion is retained while canonical product linkage remains open.

Revision
casca-factor-d-obligations-v1
Cutoff
Aug 27, 2026
Resolution
Resolve identity

Source comparison

Who said what

CISA-ADPIndependent enrichment
Record text

CISA ADP Vulnrichment

Inspect raw assertion
Field
container
Value
CISA ADP Vulnrichment
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CVE ProgramDerivative copy
Record text

CVE Program Container

Inspect raw assertion
Field
container
Value
CVE Program Container
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
ZyxelOriginal assertion
Record text

A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.

Inspect raw assertion
Field
container
Value
A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Zyxel Multiple Firewalls Buffer Overflow Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Zyxel Multiple Firewalls Buffer Overflow Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

28.14% probability · 97.96th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.281440000000; percentile 0.979630000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
92Underlying assertions
46Canonical products
69Target assertions
23Constraint assertions

Grouped from 46 configuration nodes in this exact snapshot. Visual grouping is navigational; asset exposure and root cause require cited evidence.

Identity source boundaries
  • Cpe dictionary1,775,266 records · observed through 2026-07-21T06:45:29.809Z27d65b0f-b718-4b4f-bb79-c47c68d09dfa
  • Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z955dae73-7302-438b-aee1-058d7cc5d48e

52 scope groups

Zyxel · source assertedZyxelATP series firmwareDirect source scope
Affected: 4.60 through 5.36 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 5.36 Patch 1"}]
Zyxel · source assertedZyxelUSG20(W)-VPN firmwareDirect source scope
Affected: 4.60 through 5.36 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 5.36 Patch 1"}]
Zyxel · source assertedZyxelUSG FLEX 50(W) firmwareDirect source scope
Affected: 4.60 through 5.36 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 5.36 Patch 1"}]
Zyxel · source assertedZyxelUSG FLEX series firmwareDirect source scope
Affected: 4.60 through 5.36 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 5.36 Patch 1"}]
Zyxel · source assertedZyxelVPN series firmwareDirect source scope
Affected: 4.60 through 5.36 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 5.36 Patch 1"}]
Zyxel · source assertedZyxelZyWALL/USG series firmwareDirect source scope
Affected: 4.60 through 4.73 Patch 1
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "4.60 through 4.73 Patch 1"}]
NVD CPE · HARDWAREzyxelatp100Environmental constraint · 1 assertions
Version not applicableCanonical identity product-1200899350c6986d5c964f597f369618d1abb63616766a4ba3ec511b2ebc27e6Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp100:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    0 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    7f7654a1-3806-41c7-82d4-46b0cd7ee53b
NVD CPE · OPERATING SYSTEMzyxelatp100_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-a61d6943c1bad48e17a6899eb15990b4a194af3c4c7456d58636c745ce6c0123Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp100_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    c5813b69-c1a3-4695-8b63-17994bba1723
  2. cpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    558978ad-8153-4c1f-a6de-ccfbf69f754d
  3. cpe:2.3:o:zyxel:atp100_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    b61de8a9-6a73-45ef-8c37-39138f39168a
NVD CPE · HARDWAREzyxelatp100wEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-e89e0034d5de943870101b99bf70729bdf104ab7b27b822fa2c5ad4c217de46cLinked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp100w:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    3 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    47398fd0-6c5e-4625-9efd-de08c9ab7db2
NVD CPE · OPERATING SYSTEMzyxelatp100w_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-6e8453083842a704d3eef10ca166fe4982207762b43dbd869f4d6d6da51c6519Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp100w_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    3 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    3cbaf763-195f-4b36-a450-719931b86650
  2. cpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    3 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    81cb716a-e996-48a6-8c2d-f4b9398fca77
  3. cpe:2.3:o:zyxel:atp100w_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    3 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    4cb974ec-859a-4b74-8a60-98a5406e8f43
NVD CPE · HARDWAREzyxelatp200Environmental constraint · 1 assertions
Version not applicableCanonical identity product-204c039ba605ff99a732d4aeb892002d51199a5a7289e8fc9a6195251cd09d02Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp200:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    d68a36ff-8caf-401c-9f18-94f3a2405cf4
NVD CPE · OPERATING SYSTEMzyxelatp200_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-d262d95a9d2b47c5c7875f791f3c6fa9d5d2b48a0a40750bed16cd94cd692f89Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    1 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    a32a52f5-5406-4a44-a5c1-42fcdc8c6b22
  2. cpe:2.3:o:zyxel:atp200_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    1 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    8abed29d-8074-46ab-8a0f-759b0653691b
  3. cpe:2.3:o:zyxel:atp200_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    1 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    49ff3d01-c9aa-452c-a079-3180dc8db269
NVD CPE · HARDWAREzyxelatp500Environmental constraint · 1 assertions
Version not applicableCanonical identity product-2aadc23472d0134ca1a46a96d237076a2f79c52ee591e309a631af2c09fe5858Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp500:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    2 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    2818e8ac-ffee-4df9-bf3f-c75166c0e851
NVD CPE · OPERATING SYSTEMzyxelatp500_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-51aff2d0b03d80e26b46d437c992b29e60a2d3fc16c8471fd199c9d23383d177Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp500_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    2 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    9801f3ab-4560-44aa-934f-0a6d31f46195
  2. cpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    2 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    320fc232-d76c-4d8a-8003-7c9a7a287a4c
  3. cpe:2.3:o:zyxel:atp500_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    2 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    2a0e5b17-00e0-4cb0-9787-d6a8c8e1e0be
NVD CPE · HARDWAREzyxelatp700Environmental constraint · 1 assertions
Version not applicableCanonical identity product-cea0f4a3423fb565b7fc5420cfee82db0edf528bf9235d8292671f6e8ae64fe8Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp700:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    4 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    0b41f437-855b-4490-8011-df59887be6d5
NVD CPE · OPERATING SYSTEMzyxelatp700_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-e80ae947ef2fbf604a1685f7dbf5e9c3fecc4edde631c371210a3a8519233fb1Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp700_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    4 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    f4cf847a-a858-43a6-b35b-91455682e382
  2. cpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    4 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    2360f0cc-6958-47b6-87a9-b03d52debaf8
  3. cpe:2.3:o:zyxel:atp700_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    4 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    9be980d6-9d39-41b9-a35c-1879b72f4146
NVD CPE · HARDWAREzyxelatp800Environmental constraint · 1 assertions
Version not applicableCanonical identity product-3d53771a3239415f970ae3ae39ad7aea35c319c755ea6e942a0f4add01901eb2Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp800:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    5 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    66b99746-0589-46e6-9cbd-f38619ad97dc
NVD CPE · OPERATING SYSTEMzyxelatp800_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-c0379851b411c8239197abf9661f20e966d7560c151b11c7647d2508bf2f7e92Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:atp800_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    5 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    eecc0fb9-ded8-4acf-a627-0537f3ee8c65
  2. cpe:2.3:o:zyxel:atp800_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    5 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    ba1c872c-9192-410d-86f1-55cdf07de77c
  3. cpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    5 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    6c4ee067-e0f0-49b7-8698-8b1ad8e346f0
NVD CPE · HARDWAREzyxelusg20-vpnEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-0bd1e78fe15d29edcff9915f0cb954cead37cc7f3e9a331745ef4c5f1ac121a4Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg20-vpn:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    18 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    7239c54f-ec9e-44b4-ae33-1d36e5448219
NVD CPE · OPERATING SYSTEMzyxelusg20-vpn_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-e5d0a9b1d297d36bfc243a7683973a65ca9f9b00f5fc83c43caf3713537e09eaLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    18 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    bc69fab1-c862-470a-8cbf-bb8751485611
  2. cpe:2.3:o:zyxel:usg20-vpn_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    18 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    e4194305-cca6-4710-94aa-ce0304e1aa44
  3. cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    18 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    8fd54572-2c29-4d2e-b15a-de3a16d8e3ca
NVD CPE · HARDWAREzyxelusg_20w-vpnEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-f9da0300b09cd9131de63e886e3f9279ed620453053ae48caacec872a6bcb053Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_20w-vpn:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    13 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    6bea412f-3da1-4e91-9c74-0666147dabce
NVD CPE · OPERATING SYSTEMzyxelusg_20w-vpn_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 5.36); Version 5.36Canonical identity product-41708052d4077bd8f08bf90364c85016ebd5c219f392954a84ed571d11e2981eLinked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    13 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 5.36
    Match ID
    9c0af7ba-8673-4e69-acec-8c0da8dd417b
  2. cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    13 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    107bb5b9-9c04-4c35-88ad-4d59ecd17778
  3. cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    13 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    5776089e-f9f4-4a0e-a169-fa1fc4dc6329
NVD CPE · HARDWAREzyxelusg_40Environmental constraint · 1 assertions
Version not applicableCanonical identity product-dc2434e70cc224f2b01613a8d8b3e207cd628eccb56370b9f7b02bef542e8e53Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_40:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    19 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    d84ddb81-de66-4427-8833-633b45a45a14
NVD CPE · OPERATING SYSTEMzyxelusg_40_firmwareVulnerable target · 3 assertions
Any version (unconstrained) (>= 4.60, < 4.73); Version 4.73Canonical identity product-de3d811fd5332d78ee2526236da362690657e554712055ff114d2f22d95fb0b0Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:zyxel:usg_40_firmware:4.73:patch1:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    19 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    fa798b77-d4b4-4f21-a543-a6c5aad7878f
  2. cpe:2.3:o:zyxel:usg_40_firmware:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    19 · node/0 · match 0
    Logic
    OR
    Version bounds
    from including 4.60; through excluding 4.73
    Match ID
    aef412be-51e7-4839-b5d3-c4b29dd550ce
  3. cpe:2.3:o:zyxel:usg_40_firmware:4.73:-:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    19 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    97239f61-5715-476b-bd20-b40746aafe42
NVD CPE · HARDWAREzyxelusg_40wEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-cc04a557ace4668ce5eb667c49a464ab6884df0cd1473b9ff517fdf939c0bb19Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_40w:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    20 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    8f11f36c-60db-4d81-a320-53eee43758c1

Affected-product evidence

Accepted scope and product mapping

23 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-0b2bf582a5aa79942527606012ba4ef11a68ad9abca59a4abf071acaeb96106c

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
42c316e8-7a5f-422a-a40d-67aa0f2d98c96e952ee3-50dc-4a97-a619-7d1b5c14f8cf918d8ac1-7bdf-4728-a129-d333f5818229
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-0c7537a3c4e962c61695d9a69c09c71c4706711aff73126318bc69c88e8d810d

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
2605494e-8a2c-46b5-942c-afab1f74f7ae2b7d8659-2fde-4084-a900-ee97ba6632e2c140a51d-507a-425b-a408-1f7b82f3c9f0
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-326008e6d320d68bbeba0496f28a5df816c3b4b5fd083259f33968af444d8583

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
112dd004-0f38-487e-939a-5f878f50acba7c926407-9b77-4e47-913c-07d7fcb8c254ded5834d-7b9d-4d72-8e4e-13f768650e16
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-41708052d4077bd8f08bf90364c85016ebd5c219f392954a84ed571d11e2981e

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
2f647837-fdf4-4173-b194-7837695a2c68bc4cb8f5-6e83-417b-b7cb-fc3c72f2fa32eb8445d8-fe5a-411f-b3a2-109d0798ab7c
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-51aff2d0b03d80e26b46d437c992b29e60a2d3fc16c8471fd199c9d23383d177

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
106c7c2e-dfa2-4524-a4b6-8bbbd96a449941363010-4f8d-4eff-aceb-2f9d0af108637db32257-e164-4c4e-94c3-703cd2310db6
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-5abdfb839c49688aabb3222f4bc5147ec7b4516467e598cdf06c89143c252874

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
a084f64b-857d-4307-b741-c0668ac6161ad4a81a5c-13fa-4cce-b33c-019f40dc1f54df103895-9f07-48a4-a23e-748dc4a9988b
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-6082442a6083cd87efca032eced3b7c869d191d5abe797ca758b24a14219ab98

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
0c489b77-e01d-46b9-a978-58eafc604ef4d20c77d2-4efd-4452-9149-01bf585402bbe3c817a1-68fe-4e1f-9705-d441d710430c
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-6e8453083842a704d3eef10ca166fe4982207762b43dbd869f4d6d6da51c6519

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
7263acb2-01c6-4eac-8967-ff70f4bd88947a093d59-7ebc-46ca-b23a-f7ed155e90d47c2a3c1a-1a8d-4cb6-9c27-48116f1755d5
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-73d8643b6be148d5a452006e63a97198060a54c941b1f1e4638cc41687b261d6

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
347a0416-dfd7-4c41-9a16-7f7365a2765c384f2492-650c-4469-8016-9900d79d240f65d656f8-a2fa-4d20-838c-3438f4e5275b
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-750c77056e3509254876815ce6785adb86ce7c2ee089bdf23dab5a205a9686fc

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
23206548-2457-4dc5-bba8-86beb7b08ab3a9500d02-de74-4e08-a798-cabbfb4d50e5b40067ec-b2c5-4fb5-9068-2ee5aa9b7715
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-86f99bc9ab4d50c9559bddd263642e189da788ee7e254501649990d1e1771b98

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
19dcce0f-f8c9-48c5-9002-dff9755448e7a56f841c-10e4-49f5-b0ff-68e6195a38ecb103a83f-db21-4e5a-8327-7ebd25e97131
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-936a8a7c943c7226136a60acef772ee4ce5ac143e5655c668b852f5b8d502342

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
c1afd03a-cc2f-4821-baec-d38b8115170cc9fd284b-33e7-45d5-9554-5053b0b1b33fe595b515-4907-4e79-9a78-daec5fe255dd
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-a61d6943c1bad48e17a6899eb15990b4a194af3c4c7456d58636c745ce6c0123

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
925af85a-f287-4b06-9407-084d95f71b279dc00af8-f13c-41c7-89dd-8ee764794560a3297cef-b2e8-4a36-80bf-8c52f02e296f
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-ba391e813d1ca8f48d81faa487ab68073af1b4115a2cc20d0969358c60e0f9ef

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
948f1281-3ed6-4cbc-ba99-ec4151bfaa11b5fb9e2b-ede5-416a-90ee-88789f74c27bf087e78f-5049-4945-9c1d-0e7317135d00
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-c0379851b411c8239197abf9661f20e966d7560c151b11c7647d2508bf2f7e92

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
a8b9874a-6ab7-4abe-8951-7e3124a015dfbbc78f2f-2fad-41b2-869a-d97b2344315de3d2e4b3-1e5c-4e20-bf0a-e3cc9c129db5
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-d262d95a9d2b47c5c7875f791f3c6fa9d5d2b48a0a40750bed16cd94cd692f89

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
2cfbdf33-e484-46d0-bca2-814ec9fd959e68d96677-3372-41e4-8051-3f212833d979b3f6f9cc-329f-4b33-bc84-857cb594bfef
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-d49cc06bd1694635384653ea5099d635af0950d562113257ca2b986d5033461d

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
239cf1b3-700f-4f53-8d1f-dd79cbec558359d9c751-2c59-490e-af55-47e71852fbd5d5753a84-3603-40e7-865b-27e620cb6876
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-d781087797ffcbc50b6c52eb91f3e346a66c12189f2fe0f9f13d2c13ec28c3f6

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
8f893bfc-856e-4fd0-b1d2-f09577afe56bcb2f8919-bfa0-4a9b-a3c1-06cb3a603a21dc81ef0f-553c-4e96-ae9e-fd9424a0033d
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-de3d811fd5332d78ee2526236da362690657e554712055ff114d2f22d95fb0b0

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
685a0c56-b952-4f55-b67f-8e1e63332b82baa4742d-34b2-42d6-8faa-ebde227e4465ff882a85-ade6-4a3d-a73a-50fc2520d99c
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-e09b599c8ada399dff2b8ab79fd7bbc40401bd2afbe161b152324fc7a13c2c40

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
7ccd3564-c52c-4272-b5d7-d793c659227cca0e9c78-ccd2-4bb5-a134-a2c13402ca49f70d0025-df7d-4931-a8be-4501bf957432
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-e4ca10df87762079f9b736c8c1995cdeb765fb4ad23b6ecc52f0bcca7fd863e0

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
a9a8d3ad-db95-46e4-a40d-3996b51c8522bece45ea-0244-408c-9989-50aabbe73af9f95528a3-55d7-4aea-93f0-c877adc8623f
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-e5d0a9b1d297d36bfc243a7683973a65ca9f9b00f5fc83c43caf3713537e09ea

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
9947accd-e167-4c64-8856-dbc7a6766d3fc155a2ce-46dd-476c-a903-64c5719e9cc8cfcfb3c0-36f3-49c1-a5aa-3e0587267d56
Mapping establishedEvidence supported

vendor-b18047daaf1c9692aefa2edb7182e0b8d93a7a346ff6d96ee9c363ca18b9f5cc · product-e80ae947ef2fbf604a1685f7dbf5e9c3fecc4edde631c371210a3a8519233fb1

Source class
Nvd cpe vulnerable target
Assertions
3
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
3ee00773-f80b-4c9c-9fc9-5ea2798dc4825e5eeac3-6311-40a2-af54-5b3a7910e63fd53830bc-3cf6-4580-b783-3f058537ca23
Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Direct cve affected
Assertions
6
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
01166061-9858-4bb1-8c84-ef6d1f2ca5434fc5e3b5-f7b6-4736-b3c2-a282134937556e320199-2f63-41b0-b388-4361007e6c6171edffca-ad45-469f-bbe5-0aad935da2a8ad3d9955-163f-4648-aea4-f0dbd9ed791adcd17166-4f9d-4056-846e-437f5671f13f

Assessments

CVSS by origin

9.8
NVDCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8
security@zyxel.com.twCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8
ZyxelCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Direct CVE/CNA normalized decisions

9.8Priority eligible

Zyxel

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Validation
Valid match
Recomputed
9.8
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1

Assessments are retained side by side under closed precedence. Cascade never averages CVSS.

Evidence boundaries

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; remaining scope stays source-scoped.
  • NVD-carried upstream facts remain derivative; independent corroboration requires a separately authored source.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.
  • OSV aggregation and OSV-converted NVD material are not independent corroboration.
  • Red Hat facts are vendor assertions for the exact supplied products.
  • Nonmembership and not-yet-observed states are not proof of safety.