CVE-2026-20331: Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software and Secure Firewall Management Center Software Hardening Release - Protection Mechanism Failure Vulnerabilities
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.3%
Up from 0.2% on .
EPSS score, percentile 17.7 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.6 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 9.16.1
- 9.16.1.28
- 9.16.2
- 9.16.2.3
- 9.16.2.7
- 9.16.2.11
and 30 more in the table below
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 9.16.1 |
| Affected | 9.16.1.28 |
| Affected | 9.16.2 |
| Affected | 9.16.2.3 |
| Affected | 9.16.2.7 |
| Affected | 9.16.2.11 |
| Affected | 9.16.2.13 |
| Affected | 9.16.2.14 |
| Affected | 9.16.3.3 |
| Affected | 9.16.3 |
| Affected | 9.16.3.14 |
| Affected | 9.16.3.15 |
Versions not listed are: unknown.
And 109 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | 7.0.0 |
| Affected | 7.0.0.1 |
| Affected | 7.0.1 |
| Affected | 7.0.1.1 |
| Affected | 7.0.2 |
| Affected | 7.2.0 |
| Affected | 7.0.2.1 |
| Affected | 7.0.3 |
| Affected | 7.2.0.1 |
| Affected | 7.0.4 |
| Affected | 7.2.1 |
| Affected | 7.0.5 |
Versions not listed are: unknown.
And 56 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | 7.0.0.1 |
| Affected | 7.0.1 |
| Affected | 7.0.1.1 |
| Affected | 7.0.2 |
| Affected | 7.0.2.1 |
| Affected | 7.0.3 |
| Affected | 7.0.4 |
| Affected | 7.0.5 |
| Affected | 7.3.0 |
| Affected | 7.3.1 |
| Affected | 7.0.6 |
| Affected | 7.3.1.1 |
Versions not listed are: unknown.
And 29 more version entries in the CVE record.
Source: CVE List, as of . About the data.
About this vulnerability
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 dis…
Summary: CVE record, as of .
- CISA has not added CVE-2026-20331 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 16 Sep 2026.
- The CVE record carries a CVSS v3.1 base score of 9.6 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.3% (percentile 17.7), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable no, technical impact total.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
Cisco Secure Adaptive Security Appliance Software, Secure Firewall Threat Defense Software and Secure Firewall Management Center Software Hardening Release - Protection Mechanism Failure Vulnerabilities
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-2026-20331 are related to the failure of protection mechanisms issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-693.
Source: CVE List, as of . About the data.
Weakness
CWE-693
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
References
1
Known exploited Cisco vulnerabilities
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