CVE-2025-20333: firepower threat — Actively Exploited

Description

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.

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CVSS v3.1 Score

9.9

CRITICAL

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

CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild.

Added: Sep 25, 2025 Remediation due: Sep 26, 2025

Weakness Type (CWE)

CWE-120 CWE-120

Affected Products

Vendor	Product	Versions
cisco	adaptive_security_appliance_software	9.12 — 9.12.4.72
cisco	adaptive_security_appliance_software	9.14 — 9.14.4.28
cisco	adaptive_security_appliance_software	9.16 — 9.16.4.85
cisco	adaptive_security_appliance_software	9.17.0 — 9.17.1.45
cisco	adaptive_security_appliance_software	9.18 — 9.18.4.47
cisco	adaptive_security_appliance_software	9.19 — 9.19.1.37
cisco	adaptive_security_appliance_software	9.20 — 9.20.3.7
cisco	adaptive_security_appliance_software	9.22 — 9.22.1.3
cisco	firepower_threat_defense	7.0.0 — 7.0.8.1
cisco	firepower_threat_defense	7.1.0 — 7.2.9
cisco	firepower_threat_defense	7.3.0 — 7.4.2.4
cisco	firepower_threat_defense	All

References

Advisories & Patches

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

Other References

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20333

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 9.9 (CRITICAL). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2025-20333? +

CVE-2025-20333 has a CVSS v3.1 score of 9.9 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-20333? +

CVE-2025-20333 affects products from cisco, specifically: adaptive_security_appliance_software, firepower_threat_defense. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-20333? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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