Vulnerability · Published Sep 25, 2025 · Assigned by cisco
CVE-2025-20363
Critical 9.0
In plain English
A critical-severity heap buffer overflow in Cisco Adaptive Security Appliance (ASA) Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 7.2% (higher than 94% of all known vulnerabilities).
Official 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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | IOS | 12.2(15)B12.2(16)B112.2(16)B212.2(16)B12.2(15)BC2a12.2(15)BC1a12.2(15)BC1b12.2(15)BC2d |
| Cisco | Cisco IOS XR Software | 6.5.16.5.26.5.36.6.26.6.36.6.256.7.16.7.2 |
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | 9.8.19.8.1.59.8.1.79.8.29.8.2.89.8.2.149.8.2.159.8.2.17 |
| Cisco | Cisco IOS XE Software | 3.2.0SG3.2.1SG3.2.2SG3.2.3SG3.2.4SG3.2.5SG3.2.6SG3.2.7SG |
| Cisco | Cisco Firepower Threat Defense Software | 6.2.36.2.3.16.2.3.26.2.3.36.2.3.46.2.3.56.2.3.66.2.3.7 |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H