CASCACascade Atlas

Evidence dossier

CVE-2018-0151

A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of…

Exploited in the wild (CISA KEV since Mar 3, 2022). NVD reports CVSS 3.1 9.8. EPSS estimates 14.3% exploit likelihood as of Aug 27, 2026.

74.7–76.2Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.

State
PUBLISHED
Published
Mar 28, 2018
Updated
Jan 12, 2026
Evidence coverage
95%

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
    cisco

    Record text: A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.

    Inspect raw assertion
    Field
    container
    Value
    A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.
    Original evidence ↗
  3. 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 ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 14.29% probability · 96.33th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.142870000000; percentile 0.963250000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Mar 3, 2022 · first observed Jul 19, 2026

Exploit likelihood14.29%

FIRST EPSS · score date Aug 27, 2026 · 96.3th percentile · first observed Aug 27, 2026

SeverityCVSS 9.8

NVD · 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 ↗
ciscoOriginal assertion
Record text

A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.

Inspect raw assertion
Field
container
Value
A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.
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 ↗
CISA KEVOriginal assertion
Exploitation cataloged

Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

14.29% probability · 96.33th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.142870000000; percentile 0.963250000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
2Underlying assertions
1Canonical products
2Target assertions
0Constraint assertions

Grouped from 2 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

2 scope groups

cisco · source assertedn/aCisco IOS and IOS XEDirect source scope
Affected: Cisco IOS and IOS XE
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "Cisco IOS and IOS XE"}]
NVD CPE · OPERATING SYSTEMciscoios_xeVulnerable target · 2 assertions
Version 16.5.1; Version not applicableCanonical identity product-cc06181059d0f387414dd5737700c03a38fe93d65d4a541ac9744a37c25c9f59Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:o:cisco:ios_xe:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    1 · node/0 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    b7d95e8a-8f0b-44e5-b266-09e10baaec55
  2. cpe:2.3:o:cisco:ios_xe:16.5.1:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    fe7b2557-821d-4e05-b5c3-67192573d97d

Affected-product evidence

Accepted scope and product mapping

1 canonical links · 1 source-reported links

Mapping establishedEvidence supported

vendor-0774b265c0e837e737aaf99ed0f2450c048e61f34267ca59d8623878b839334e · product-cc06181059d0f387414dd5737700c03a38fe93d65d4a541ac9744a37c25c9f59

Source class
Nvd cpe vulnerable target
Assertions
2
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
50a1e4dc-57d6-4232-9ba3-c13a052037a6c9aaf348-361a-430c-a682-e8b212960142
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
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
57667098-3f9c-4102-8999-d9f8ccbf53da

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
10.0
NVDCVSS 2.0 · role Primary · priority eligiblevalid_matchAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8
CVE Program sourceCVSS 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
CISA-ADPCVSS 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

CISA-ADP

CVSS 3.1 · Secondary · Independent enrichment · rank 2

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.