Answer in brief
CVE-2026-20271 records a High severity (CVSS 8.6) vulnerability in Cisco IOS XE Software Security Hardening Release. The current sources do not mark it as known exploited. The current feed maps Cisco/Cisco IOS XE Software (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Cisco/Cisco IOS XE Software (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco IOS XE Softwaregeneric | 17.2.1a || 16.12.1y || 16.12.3s || 16.7.1b || 16.6.2 || 16.6.5 || 16.12.1w || 16.9.1d || 17.3.1 || 16.9.4c || 16.7.1 || 17.2.1 || 16.6.8 || 16.9.1b || 16.9.2s || 16.12.4 || 16.12.3a || 17.1.1s || 16.11.1a || 16.7.2 || 16.11.1b || 16.9.1s || 16.9.3h || 16.9.1c || 16.6.5a || 16.6.3 || 16.10.1f || 17.2.1v || 16.8.1e || 16.9.3a || 16.12.1a || 16.12.1x || 16.6.4s || 16.10.1c || 16.12.3 || 16.11.2 || 16.6.5b || 16.12.2s || 16.10.1b || 16.7.3 || 16.6.7 || 16.9.6 || 16.9.2 || 16.10.1 || 16.12.1t || 16.9.1 || 16.8.1a || 16.9.3s || 16.6.7a || 16.12.2 || 16.11.1 || 16.9.3 || 16.11.1s || 16.12.1 || 17.1.1 || 17.1.2 || 16.10.1d || 17.1.1t || 16.9.4 || 16.8.3 || 16.12.2t || 16.9.5 || 16.8.1s || 16.10.1e || 16.8.2 || 16.6.4 || 16.8.1b || 16.10.1a || 16.12.1z || 16.8.1c || 16.9.1a || 16.9.5f || 16.6.4a || 16.10.1g || 16.8.1 || 16.6.6 || 16.9.2a || 16.8.1d || 16.10.3 || 16.7.1a || 16.11.1c || 16.10.1s || 17.2.1r || 17.1.1a || 16.10.2 || 16.12.2a || 16.12.1c || 16.12.1s || 16.7.4 || 17.2.2 || 16.9.8 || 16.9.7 || 17.1.3 || 17.3.1a || 17.3.2a || 16.12.5 || 17.3.1w || 17.3.2 || 17.4.1 || 16.12.4a || 17.4.1a || 17.3.1x || 17.3.3 || 16.6.9 || 17.2.3 || 17.5.1 || 16.12.1z1 || 16.12.5a || 17.4.1b || 17.3.1z || 16.12.5b || 17.4.2 || 17.3.3a || 17.3.5 || 17.3.4 || 17.5.1a || 16.12.6 || 17.6.1 || 16.12.1z2 || 16.6.10 || 17.3.4a || 17.6.1a || 17.7.1 || 17.6.1x || 17.6.2 || 16.12.6a || 17.3.4c || 17.4.2a || 17.3.4b || 17.7.1a || 16.12.7 || 17.8.1a || 17.6.3a || 17.6.3 || 17.7.2 || 17.7.1b || 17.9.1w || 17.3.5a || 17.6.1z || 16.12.8 || 17.8.1 || 17.9.1 || 17.6.4 || 17.3.5b || 17.9.1a || 17.3.6 || 17.10.1 || 16.9.8a || 17.6.1z1 || 17.10.1a || 17.9.2 || 17.6.5 || 17.9.1x || 17.9.1y || 16.9.8b || 17.3.7 || 17.9.2a || 17.9.3 || 16.12.9 || 17.11.1 || 17.10.1b || 17.6.6 || 17.9.1x1 || 17.11.1a || 17.9.3a || 17.12.1 || 17.3.8 || 17.9.4 || 16.12.10 || 17.12.1w || 17.9.1y1 || 17.12.1a || 17.9.5 || 17.13.1 || 17.12.1x || 17.12.2 || 17.14.1 || 17.9.4a || 17.3.8a || 17.6.6a || 17.6.5a || 17.6.7 || 16.12.10a || 17.15.1 || 17.13.1a || 17.12.2a || 16.12.11 || 17.12.3 || 17.12.1y || 17.12.1z || 17.9.5a || 17.14.1a || 17.9.5b || 17.6.8 || 16.12.12 || 17.12.4 || 17.9.6 || 17.17.1 || 17.16.1 || 17.15.1w || 17.12.3a || 17.9.5c || 17.15.1a || 17.12.1z1 || 17.15.2 || 17.15.1b || 17.9.5d || 17.15.1x || 17.9.6a || 17.12.1z2 || 17.6.8a || 17.16.1a || 16.12.13 || 17.15.3 || 17.9.7 || 17.12.5 || 17.15.1y || 17.9.5e || 17.12.4a || 17.15.2a || 17.15.2c || 17.15.2b || 17.12.1z3 || 17.9.5f || 17.12.4b || 17.12.5a || 17.18.1 || 17.12.6 || 17.12.1z4 || 17.9.8 || 17.9.7a || 17.15.3a || 17.15.4 || 17.12.5b || 17.15.3b || 16.12.14 || 17.18.1z || 17.9.7b || 17.12.5c || 26.1.1 || 17.18.1a || 17.15.4a || 17.18.2 || 17.18.1w || 17.15.4b || 17.12.6a || 17.12.7 || 17.15.4c || 17.9.9 || 17.12.5d || 16.12.15 || 17.15.4s1 || 17.15.5 || 17.12.1z5 || 17.18.1x || 17.12.1z6 || 17.15.4d || 17.12.6b || 17.4.1c || 17.15.5a || 17.18.1y || 17.12.7a || 17.18.3 || 17.12.7b || 17.18.3a || 26.1.1a || 17.15.7 || 16.12.16 | Not reported |
Published upstream
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20271 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-691.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-20271 records a High severity (CVSS 8.6) vulnerability in Cisco IOS XE Software Security Hardening Release. The current sources do not mark it as known exploited. The current feed maps Cisco/Cisco IOS XE Software (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Cisco/Cisco IOS XE Software (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Cisco/Cisco IOS XE Softwaregeneric | 17.2.1a || 16.12.1y || 16.12.3s || 16.7.1b || 16.6.2 || 16.6.5 || 16.12.1w || 16.9.1d || 17.3.1 || 16.9.4c || 16.7.1 || 17.2.1 || 16.6.8 || 16.9.1b || 16.9.2s || 16.12.4 || 16.12.3a || 17.1.1s || 16.11.1a || 16.7.2 || 16.11.1b || 16.9.1s || 16.9.3h || 16.9.1c || 16.6.5a || 16.6.3 || 16.10.1f || 17.2.1v || 16.8.1e || 16.9.3a || 16.12.1a || 16.12.1x || 16.6.4s || 16.10.1c || 16.12.3 || 16.11.2 || 16.6.5b || 16.12.2s || 16.10.1b || 16.7.3 || 16.6.7 || 16.9.6 || 16.9.2 || 16.10.1 || 16.12.1t || 16.9.1 || 16.8.1a || 16.9.3s || 16.6.7a || 16.12.2 || 16.11.1 || 16.9.3 || 16.11.1s || 16.12.1 || 17.1.1 || 17.1.2 || 16.10.1d || 17.1.1t || 16.9.4 || 16.8.3 || 16.12.2t || 16.9.5 || 16.8.1s || 16.10.1e || 16.8.2 || 16.6.4 || 16.8.1b || 16.10.1a || 16.12.1z || 16.8.1c || 16.9.1a || 16.9.5f || 16.6.4a || 16.10.1g || 16.8.1 || 16.6.6 || 16.9.2a || 16.8.1d || 16.10.3 || 16.7.1a || 16.11.1c || 16.10.1s || 17.2.1r || 17.1.1a || 16.10.2 || 16.12.2a || 16.12.1c || 16.12.1s || 16.7.4 || 17.2.2 || 16.9.8 || 16.9.7 || 17.1.3 || 17.3.1a || 17.3.2a || 16.12.5 || 17.3.1w || 17.3.2 || 17.4.1 || 16.12.4a || 17.4.1a || 17.3.1x || 17.3.3 || 16.6.9 || 17.2.3 || 17.5.1 || 16.12.1z1 || 16.12.5a || 17.4.1b || 17.3.1z || 16.12.5b || 17.4.2 || 17.3.3a || 17.3.5 || 17.3.4 || 17.5.1a || 16.12.6 || 17.6.1 || 16.12.1z2 || 16.6.10 || 17.3.4a || 17.6.1a || 17.7.1 || 17.6.1x || 17.6.2 || 16.12.6a || 17.3.4c || 17.4.2a || 17.3.4b || 17.7.1a || 16.12.7 || 17.8.1a || 17.6.3a || 17.6.3 || 17.7.2 || 17.7.1b || 17.9.1w || 17.3.5a || 17.6.1z || 16.12.8 || 17.8.1 || 17.9.1 || 17.6.4 || 17.3.5b || 17.9.1a || 17.3.6 || 17.10.1 || 16.9.8a || 17.6.1z1 || 17.10.1a || 17.9.2 || 17.6.5 || 17.9.1x || 17.9.1y || 16.9.8b || 17.3.7 || 17.9.2a || 17.9.3 || 16.12.9 || 17.11.1 || 17.10.1b || 17.6.6 || 17.9.1x1 || 17.11.1a || 17.9.3a || 17.12.1 || 17.3.8 || 17.9.4 || 16.12.10 || 17.12.1w || 17.9.1y1 || 17.12.1a || 17.9.5 || 17.13.1 || 17.12.1x || 17.12.2 || 17.14.1 || 17.9.4a || 17.3.8a || 17.6.6a || 17.6.5a || 17.6.7 || 16.12.10a || 17.15.1 || 17.13.1a || 17.12.2a || 16.12.11 || 17.12.3 || 17.12.1y || 17.12.1z || 17.9.5a || 17.14.1a || 17.9.5b || 17.6.8 || 16.12.12 || 17.12.4 || 17.9.6 || 17.17.1 || 17.16.1 || 17.15.1w || 17.12.3a || 17.9.5c || 17.15.1a || 17.12.1z1 || 17.15.2 || 17.15.1b || 17.9.5d || 17.15.1x || 17.9.6a || 17.12.1z2 || 17.6.8a || 17.16.1a || 16.12.13 || 17.15.3 || 17.9.7 || 17.12.5 || 17.15.1y || 17.9.5e || 17.12.4a || 17.15.2a || 17.15.2c || 17.15.2b || 17.12.1z3 || 17.9.5f || 17.12.4b || 17.12.5a || 17.18.1 || 17.12.6 || 17.12.1z4 || 17.9.8 || 17.9.7a || 17.15.3a || 17.15.4 || 17.12.5b || 17.15.3b || 16.12.14 || 17.18.1z || 17.9.7b || 17.12.5c || 26.1.1 || 17.18.1a || 17.15.4a || 17.18.2 || 17.18.1w || 17.15.4b || 17.12.6a || 17.12.7 || 17.15.4c || 17.9.9 || 17.12.5d || 16.12.15 || 17.15.4s1 || 17.15.5 || 17.12.1z5 || 17.18.1x || 17.12.1z6 || 17.15.4d || 17.12.6b || 17.4.1c || 17.15.5a || 17.18.1y || 17.12.7a || 17.18.3 || 17.12.7b || 17.18.3a || 26.1.1a || 17.15.7 || 16.12.16 | Not reported |
Published upstream
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20271 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-691.
Quoted source text, attributed separately from HOL analysis.