CASCACascade Atlas

Evidence dossier

CVE-2024-11667

A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through…

Exploited in the wild (CISA KEV since Dec 3, 2024). NVD reports CVSS 3.1 9.8. Severity assessments differ within at least one CVSS version. EPSS estimates 3.0% exploit likelihood as of Aug 27, 2026.

62.2–77.7Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.

State
PUBLISHED
Published
Nov 27, 2024
Updated
Aug 5, 2026
Evidence coverage
72%

Evidence chronology

What was known when

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  1. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Zyxel Multiple Firewalls Path Traversal Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Zyxel Multiple Firewalls Path Traversal Vulnerability
    Original evidence ↗
  2. 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 ↗
  3. Source dateSource date omittedFirst observed by CASCA
    Zyxel

    Record text: A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.

    Inspect raw assertion
    Field
    container
    Value
    A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 2.99% probability · 86.34th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.029920000000; percentile 0.863400000000
    Original evidence ↗

Assessments differ

NVD9.8CVSS 3.1 · source date omitted
security@zyxel.com.tw7.5CVSS 3.1 · source date omitted

Values are shown separately by source and CVSS version.

ExploitationCatalog member

CISA KEV · catalog date Dec 3, 2024 · first observed Jul 19, 2026

Exploit likelihood2.99%

FIRST EPSS · score date Aug 27, 2026 · 86.3th percentile · first observed Aug 27, 2026

SeverityAssessments differ

NVD · CVSS 3.1 · first observed Aug 6, 2026 · values shown separately below

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 assessmentAssessments differ

Eligible assertions materially conflict and remain visible side by side.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
Resolve conflict
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 KEVOriginal assertion
Exploitation cataloged

Zyxel Multiple Firewalls Path Traversal Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Zyxel Multiple Firewalls Path Traversal Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
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 ↗
ZyxelOriginal assertion
Record text

A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.

Inspect raw assertion
Field
container
Value
A directory traversal vulnerability in the web management interface of Zyxel ATP series firmware versions V5.00 through V5.38, USG FLEX series firmware versions V5.00 through V5.38, USG FLEX 50(W) series firmware versions V5.10 through V5.38, and USG20(W)-VPN series firmware versions V5.10 through V5.38 could allow an attacker to download or upload files via a crafted URL.
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

2.99% probability · 86.34th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.029920000000; percentile 0.863400000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
21Underlying assertions
18Canonical products
4Target assertions
17Constraint assertions

Grouped from 8 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

26 scope groups

CISA-ADP · source assertedzyxelatp_firmwareDirect source scope
Affected: 5.00 through 5.38 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "5.00", "versionType": "custom", "lessThanOrEqual": "5.38"}]
CISA-ADP · source assertedzyxelusg20-vpn_firmwareDirect source scope
Affected: 5.10 through 5.38 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "5.10", "versionType": "custom", "lessThanOrEqual": "5.38"}]
CISA-ADP · source assertedzyxelusg_flex_50w_firmwareDirect source scope
Affected: 5.10 to before 5.38 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "5.10", "lessThan": "5.38", "versionType": "custom"}]
CISA-ADP · source assertedzyxelusg_flex_firmwareDirect source scope
Affected: 5.00 through 5.38 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "5.00", "versionType": "custom", "lessThanOrEqual": "5.38"}]
Zyxel · source assertedZyxelATP series firmwareDirect source scope
Affected: versions V5.00 through V5.38
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "versions V5.00 through V5.38"}]
Zyxel · source assertedZyxelUSG20(W)-VPN series firmwareDirect source scope
Affected: versions V5.10 through V5.38
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "versions V5.10 through V5.38"}]
Zyxel · source assertedZyxelUSG FLEX 50(W) series firmwareDirect source scope
Affected: versions V5.10 through V5.38
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "versions V5.10 through V5.38"}]
Zyxel · source assertedZyxelUSG FLEX series firmwareDirect source scope
Affected: versions V5.00 through V5.38
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "versions V5.00 through V5.38"}]
NVD CPE · HARDWAREzyxelatpEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-a814f770e5a64567fb05e9d5efb7456e96862f8246dc55ab5baba29eb96663caLinked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:atp:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    0 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    788b28b2-e2ee-4d98-8862-15b121009b6e
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 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    7f7654a1-3806-41c7-82d4-46b0cd7ee53b
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
    0 · node/1 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    47398fd0-6c5e-4625-9efd-de08c9ab7db2
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
    0 · node/1 · match 3
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    d68a36ff-8caf-401c-9f18-94f3a2405cf4
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
    0 · node/1 · match 4
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    2818e8ac-ffee-4df9-bf3f-c75166c0e851
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
    0 · node/1 · match 5
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    0b41f437-855b-4490-8011-df59887be6d5
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
    0 · node/1 · match 6
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    66b99746-0589-46e6-9cbd-f38619ad97dc
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
    3 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    6bea412f-3da1-4e91-9c74-0666147dabce
NVD CPE · HARDWAREzyxelusg_flexEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-ad531a55d48c65893035c5ceec4368e0a24a3753ba68e0fe74c6e885d9285956Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    e4edcc3c-8ee5-43d3-8739-34987f025df2
NVD CPE · HARDWAREzyxelusg_flex_100Environmental constraint · 1 assertions
Version not applicableCanonical identity product-70213505d2b8f408c480cab89b9ac09b5fe0d081880dce71e2b038b5834e0be1Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    2b30a4c0-9928-46ad-9210-c25656fb43fb
NVD CPE · HARDWAREzyxelusg_flex_100axEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-a1e597f9eca283169e4487b8301c9b4fdeefbf638503d7b4e4df3e1fd59ac1c3Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_100ax:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    03036815-04ae-4e39-8310-da19a32cfa48
NVD CPE · HARDWAREzyxelusg_flex_100wEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-e64f051566e72ee8abc4c7cf7c156e863ad218d5c276e00ed48e367f76fc3301Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 3
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    d74aba7e-aa78-4a13-a64e-c44021591b42
NVD CPE · HARDWAREzyxelusg_flex_200Environmental constraint · 1 assertions
Version not applicableCanonical identity product-186ec2e7e83ecc39c0cd4f4aab725cf56a83377b1b1f4e40d0fefce00e4a9d1cLinked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 4
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    f93b6a06-2951-46d2-a7e1-103d7318d612
NVD CPE · HARDWAREzyxelusg_flex_50Environmental constraint · 1 assertions
Version not applicableCanonical identity product-7025caa2dd69d9529684ecd695318b3af50756e32c1568668375fa72f8cddf26Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 5
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    646c1f07-b553-47b0-953b-dc7de7fd0f8b
NVD CPE · HARDWAREzyxelusg_flex_500Environmental constraint · 1 assertions
Version not applicableCanonical identity product-afda088bf23ac862c272dd4f5b5f3637e058cc2d39deaa00cbf718d11c5a5293Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 6
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    92c697a5-d1d3-4ff0-9c43-d27b18181958
NVD CPE · HARDWAREzyxelusg_flex_50wEnvironmental constraint · 1 assertions
Version not applicableCanonical identity product-c98c837429b0a3aabe411f843bea6a70eb823fac1a98eda667a919cbbd0b46beLinked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    2 · node/1 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    110a1ca4-0170-4834-8281-0a3e14fc5584
NVD CPE · HARDWAREzyxelusg_flex_700Environmental constraint · 1 assertions
Version not applicableCanonical identity product-f6e93fd108e93ab36a3a91acddd9cd6c1468ff478c0d4161435afa92f05663d7Linked exact
Scope constrained
Inspect raw assertion
  1. cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Environmental constraint
    Configuration
    1 · node/1 · match 7
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    9d1396e3-731b-4d05-a3f8-f3abb80d5c29

Affected-product evidence

Accepted scope and product mapping

0 canonical links · 2 source-reported links

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
8
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
1b7b563e-59e5-4230-86df-fd3d55c9f5c93514ebeb-164d-48f2-a45e-3953320f4b3b4004841c-d1ea-4738-9bc8-b4cd087013ec51528c7a-d6c2-47d4-bbc5-c0db3aaa3cc751bf2e9d-5aac-4b35-b18c-f2560c3fa10eb30aac4a-399b-49ec-b59e-a81d1762aa36eb4da30a-505f-49b4-ae1e-351104ae42c2f64f4fab-8070-40b1-b602-609d1720c101
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
Nvd cpe vulnerable target
Assertions
4
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
8394dbaa-ac35-4075-ad15-257c0b74fac2ac82e022-53b5-42d3-a9b7-e9cd5ae6c91cde8d404a-6c0f-4db4-91fe-021a428d5891dfc0e5f5-656a-41d9-b911-32ee7c0356c8

Assessments

CVSS by origin

9.8
NVDCVSS 3.1 · role Primary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5
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:N/A:N
7.5
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:N/A:N

Direct CVE/CNA normalized decisions

7.5Priority 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:N/A:N
Validation
Valid match
Recomputed
7.5
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.