CVE-2025-20359
Multiple Cisco Products Snort 3 MIME Information Disclosure or Denial of Service Vulnerability
Description
Multiple Cisco products are affected by a vulnerability in the Snort 3 HTTP Decoder that could allow an unauthenticated, remote attacker to cause the disclosure of possible sensitive data or cause the Snort 3 Detection Engine to crash. This vulnerability is due to an error in the logic of buffer handling when the MIME fields of the HTTP header are parsed. This can result in a buffer under-read. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to induce one of two possible outcomes: the unexpected restarting of the Snort 3 Detection Engine, which could cause a denial of service (DoS) condition, or information disclosure of sensitive information in the Snort 3 data stream. Due to the under-read condition, it is possible that sensitive information that is not valid connection data could be returned.
Weakness: CWE-127
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Cyber Vision | OT / IoT Security | cna-assigner |
| Cisco | Cisco Firepower Threat Defense (FTD) Check your version | Firewall / NGFW | cna-assigner |
| Cisco | Cisco UTD SNORT IPS Engine | Threat Detection & Sandbox | cna-assigner |
Vendor-reported products (3)
- Cisco · Cisco Cyber Vision
- Cisco · Cisco Secure Firewall Threat Defense (FTD) Software
- Cisco · Cisco UTD SNORT IPS Engine Software
Vendor advisory
cisco-sa-snort3-mime-vulns-tTL8PgVH
Multiple Cisco Products Snort 3 MIME Denial of Service Vulnerabilities
Cisco’s rating: Medium (advisory CVSS 6.5) · Published Oct 15, 2025 · updated Feb 12, 2026 (revision 1.1)
Bug IDs: CSCwo71401 , CSCwq03467 , CSCwq15864 , CSCwq42141 , CSCwq42153 , CSCwq42161
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from