CVE-2025-20363

CRITICAL

Published Sep 25, 2025 Modified Feb 10, 2026 CWE-122

Description

A vulnerability in the web services of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall Threat Defense (FTD) Software, Cisco IOS Software, Cisco IOS XE Software, and Cisco IOS XR Software could allow an unauthenticated, remote attacker (Cisco ASA and FTD Software) or authenticated, remote attacker (Cisco IOS, IOS XE, and IOS XR Software) with low user privileges to execute arbitrary code on an affected device. This vulnerability is due to improper validation of user-supplied input in HTTP requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web service on an affected device after obtaining additional information about the system, overcoming exploit mitigations, or both. A successful exploit could allow the attacker to execute arbitrary code as root, which may lead to the complete compromise of the affected device. For more information about this vulnerability, see the Details ["#details"] section of this advisory.

CVSS v3.1 Score

9.0

CRITICAL

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

Weakness Type (CWE)

CWE-122 CWE-122

Affected Products

Vendor	Product	Versions
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	asr_9001	All
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 — 9.16.4.84
cisco	adaptive_security_appliance_software	9.17.1 — 9.18.4.57
cisco	adaptive_security_appliance_software	9.19.1 — 9.19.1.42
cisco	adaptive_security_appliance_software	9.20.1 — 9.20.3.16
cisco	adaptive_security_appliance_software	9.22 — 9.22.2
cisco	adaptive_security_appliance_software	9.23 — 9.23.1.3
cisco	ios	12.2\(15\)b — 15.9\(3\)m11
cisco	ios_xe	3.2.0sg — 17.17.1
cisco	firepower_threat_defense	7.0.0 — 7.0.8
cisco	firepower_threat_defense	7.1.0 — 7.2.10
cisco	firepower_threat_defense	7.3.0 — 7.4.2.3
cisco	firepower_threat_defense	7.7.0 — 7.7.10
cisco	firepower_threat_defense	All

References

Advisories & Patches

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http-code-exec-WmfP3h3O

Frequently Asked Questions

What is CVE-2025-20363? +

How severe is CVE-2025-20363? +

CVE-2025-20363 has a CVSS v3.1 score of 9.0 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-20363? +

CVE-2025-20363 affects products from cisco, specifically: adaptive_security_appliance_software, asr_9001, firepower_threat_defense, ios, ios_xe, ios_xr. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-20363? +

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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