CVE-2025-20333

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 authenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker with valid VPN user credentials could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as root, possibly resulting in the complete compromise of the affected device.

CVSS 3.1

9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

71% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-25)

CISA KEV

listed 2025-09-25, due 2025-09-26

CWE

CWE-120

Published

2025-09-25

Modified

2026-10-18

Record from

the NVD, synced 2026-10-19

Affected

• cisco:adaptive_security_appliance_software
• cisco:secure_firewall_threat_defense

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-webvpn-z5xP8EUB
• https://sec.cloudapps.cisco.com/security/center/resources/asa_ftd_continued_attacks
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20333

Check your stackJSON