CVE-2026-20329

CRITICALPre-NVD 9.99.9—
EchelonGraph scoreHIGH confidence

Score 9.9 from GitHub Security Advisory (severity: CRITICAL) published 2026-09-16. a secondary CVSS source baseline 9.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.9EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.9Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense Software and Cisco Secure Firewall Management Center Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-20329 are related to issues concerning improper handling of exceptional conditions that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-703.

CVSS v3
9.9
EG Score
9.9(high)
EG Risk
45(Track)
EG Risk 45/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity99% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
38%
KEV
Not listed

Published

September 16, 2026

Last Modified

September 18, 2026

Advisory Details (1)

Auto-updated Sep 18, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic🔴 Active Exploitation

Cisco Secure Firewall Adaptive Security Appliance, Secure Firewall Threat Defense, and Secure Firewall Management Center Software Hardening Release: September 2026

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-asaftdfmc-uvpPROhN

Vendor Advisories for CVE-2026-20329(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 31× in last 7d / 31× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 08:35 UTCGHSA enrichment
  2. 2026-09-19 04:35 UTCGHSA enrichment
  3. 2026-09-19 00:34 UTCGHSA enrichment
  4. 2026-09-18 20:35 UTCEG score recompute
  5. 2026-09-18 20:35 UTCGHSA enrichment
  6. 2026-09-18 19:27 UTCEPSS rescore
  7. 2026-09-18 19:20 UTCEG score recompute
  8. 2026-09-18 19:20 UTCGHSA enrichment
  9. 2026-09-18 16:34 UTCGHSA enrichment
  10. 2026-09-18 12:34 UTCGHSA enrichment
  11. 2026-09-18 08:34 UTCGHSA enrichment
  12. 2026-09-18 04:35 UTCEG score recompute
  13. 2026-09-18 04:35 UTCGHSA enrichment
  14. 2026-09-18 04:04 UTCEG score recompute
  15. 2026-09-18 04:04 UTCGHSA enrichment
  16. 2026-09-18 03:43 UTCGHSA enrichment
  17. 2026-09-17 23:44 UTCEG score recompute
  18. 2026-09-17 23:44 UTCGHSA enrichment
  19. 2026-09-17 19:23 UTCGHSA enrichment
  20. 2026-09-17 15:24 UTCEG score recompute
  21. 2026-09-17 15:24 UTCGHSA enrichment
  22. 2026-09-17 15:04 UTCEG score recompute
  23. 2026-09-17 15:04 UTCGHSA enrichment
  24. 2026-09-17 12:59 UTCGHSA enrichment
  25. 2026-09-17 08:59 UTCGHSA enrichment
Show 6 more
  1. 2026-09-17 04:59 UTCGHSA enrichment
  2. 2026-09-17 00:59 UTCEG score recompute
  3. 2026-09-17 00:59 UTCGHSA enrichment
  4. 2026-09-16 20:32 UTCEG score recompute
  5. 2026-09-16 20:09 UTCEG score recompute
  6. 2026-09-16 20:09 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-20329?
CVE-2026-20329 is a critical vulnerability published on September 16, 2026. As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense Software and Cisco Secure Firewall Management Center Software engineering team has conducted a comprehensive internal security…
When was CVE-2026-20329 disclosed?
CVE-2026-20329 was first published in the National Vulnerability Database on September 16, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-20329 actively exploited?
CVE-2026-20329 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 61.9% of all scored CVEs.
What is the CVSS score of CVE-2026-20329?
CVE-2026-20329 has a CVSS v3 base score of 9.9 (NVD).
How do I remediate CVE-2026-20329?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-20329, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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