CVE-2025-20362
Description
Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTD Software releases that are affected by CVE-2025-20333 and CVE-2025-20362. This attack can cause unpatched devices to unexpectedly reload, leading to denial of service (DoS) conditions. Cisco strongly recommends that all customers upgrade to the fixed software releases that are listed in the Fixed Software ["#fs"] section of this advisory. A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to access restricted URL endpoints that are related to remote access VPN that should otherwise be inaccessible without authentication. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web server on a device. A successful exploit could allow the attacker to access a restricted URL without authentication.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
4- Cisco Systems, Inc./Adaptive Security Appliance Cx Context Aware Security Softwarellm-fuzzy2 versions
(expand)+ 1 more
- (no CPE)
- (no CPE)range: 9.8.1
(expand)+ 1 more
- (no CPE)
- (no CPE)range: 6.2.3
Patches
Vulnerability mechanics
References
1News mentions
7- Russian Threat Groups Use RDP, VPN, Supply Chain Attacks, and Social Engineering for Initial AccessCyber Security News · May 22, 2026
- New Cisco DoS flaw requires manual reboot to revive devicesBleepingComputer · May 6, 2026
- ⚡ Weekly Recap: Fast16 Malware, XChat Launch, Federal Backdoor, AI Employee Tracking & MoreThe Hacker News · Apr 27, 2026
- FIRESTARTER Backdoor Hit Federal Cisco Firepower Device, Survives Security PatchesThe Hacker News · Apr 24, 2026
- It pays to be a forever studentCisco Talos Intelligence · Apr 23, 2026
- UAT-4356's Targeting of Cisco Firepower DevicesCisco Talos Intelligence · Apr 23, 2026
- FIRESTARTER BackdoorCISA Alerts