- High 8.6
- Known exploited (CISA KEV)
CVE-2026-20349
A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient error checking when processing HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker…
Scores
The facts
- Published
- 11 August 2026
- Last changed
- 16 September 2026
- NVD status
- Analyzed
- Severity
- High, CVSS 8.6 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H - Weakness
- Affects
- cisco adaptive security appliance software
- cisco secure firewall threat defense
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 11 August 2026.
- EPSS
- 1.0% chance of exploitation activity in the next 30 days (percentile 63).
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