Cisco Adaptive Security Appliance (ASA) Software: Improper Validation of Specified Type of Input
CVE-2025-20244 is a high-severity improper validation of specified type of input vulnerability in Cisco Adaptive Security Appliance (ASA) Software from Cisco, with a CVSS 3.1 base score of 7.7 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Cisco Adaptive Security Appliance (ASA) Software versions: 9.12.3; 9.8.3; 9.12.1, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.55% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Cisco Adaptive Security Appliance (ASA) Software you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | 9.12.3; 9.8.3; 9.12.1; 9.8.1; 9.12.2; 9.8.2.45; 9.8.2; 9.8.4; and 32 more ranges | Not stated |
| Cisco | Cisco Firepower Threat Defense Software | 6.2.3.14; 6.4.0.1; 6.2.3.7; 6.2.3; 6.4.0.2; 6.2.3.9; 6.2.3.1; 6.2.3.2; and 32 more ranges | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H. Scored by CNA (cisco.com).
Official description
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 a remote attacker that is authenticated as a VPN user to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to incomplete error checking when parsing an HTTP header field value. An attacker could exploit this vulnerability by sending a crafted HTTP request to a targeted Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause a DoS condition, which would cause the affected device to reload.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Specified Type of Input
The product receives input that is expected to be of a certain type, but it does not validate or incorrectly validates that the input is actually of the expected type.
More Improper Validation of Specified Type of Input vulnerabilities (CWE-1287)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software
- 9.0 Critical severity
- 8.6 High severity
- 8.6 High severity
- 8.5 High severity
- 8.6 High severity
- 8.6 High severity
Recent Improper Validation of Specified Type of Input vulnerabilities
- 8.7 High severity
- 8.7 High severity
- 7.5 High severity
- 7.5 High severity
- 8.2 High severity
- 7.5 High severity
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