Cisco Adaptive Security Appliance and Firepower Threat Defense: Unauthorized Access (CVE-2023-20269)
Cisco Adaptive Security Appliance and Firepower Threat Defense
Cisco Adaptive Security Appliance and Firepower Threat Defense contain an unauthorized access vulnerability that could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or establish a clientless SSL VPN session with an unauthorized user. Added to CISA KEV on 2023-09-13. CISA lists known use in ransomware campaigns.
Why this severity: CVSS 9.1 (NVD), actively exploited (CISA KEV), known ransomware use
- Started
- Sep 13, 2023
- Closed
- Sep 13, 2023
Affected
- See vendor advisory / CISA notes (versions not always listed in KEV feed)
Fixed in
- See vendor advisory linked in sources
Timeline1
CISA added CVE-2023-20269 to the KEV catalog (due 2023-10-04).
Advisories3
Notes & caveats
Derived from CISA KEV JSON feed catalogVersion 2026.10.21. Exact affected/fixed version strings are not always in the KEV record — verify against the vendor advisory URL. startedAt uses dateAdded (exploitation may have begun earlier).
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