CVE-2026-20330: Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · Improper Neutralization
Affects Cisco Secure Firewall Adaptive Security Appliance (ASA) SoftwareSource CVE Database V5
Not known to be exploited · CVSS 9.9 Critical.
Data as of 31 Oct 2026, 20:20 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 31 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| CiscoCisco Secure Firewall Adaptive Security Appliance (ASA) Software | Affected
| Fixed in– |
| CiscoCisco Secure Firewall Management Center (FMC) | Affected
| Fixed in– |
| CiscoCisco Secure Firewall Threat Defense (FTD) Software | Affected
| Fixed in– |
AI-suggested
Cisco has released a software hardening update that addresses these vulnerabilities as part of their internal security review process. Users should apply the official Cisco patches or updates corresponding to their affected ASA software versions. Since this is not a cloud service, remediation depends on applying vendor-provided updates. Patch status is not explicitly confirmed in the provided data; therefore, check Cisco's official advisory for the latest remediation guidance.
Description
CVE-2026-20330 is a critical vulnerability in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software involving improper neutralization issues classified under CWE-707. This vulnerability affects multiple specific versions of the ASA software. It has a very high CVSS score of 9.9, indicating network exploitable conditions with low attack complexity, requiring low privileges, and no user interaction, resulting in high confidentiality, integrity, and availability impacts. No public exploits are known at this time, and the vulnerability was identified through Cisco's internal security review process.