CVE-2026-20052
Cisco Secure Firewall Threat Defense Software Snort 3 Memory Management Denial of Service Vulnerability
Description
A vulnerability in the memory management handling for the Snort 3 Detection Engine of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart. This vulnerability is due to a logic error in memory management when a device is performing Snort 3 SSL packet inspection. An attacker could exploit this vulnerability by sending crafted SSL packets through an established connection to be parsed by the Snort 3 Detection Engine. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine unexpectedly restarts.
Weakness: CWE-788
Affected products
| Vendor | Product | Category | Matched by |
|---|---|---|---|
| Cisco | Cisco Firepower Threat Defense (FTD) Check your version | Firewall / NGFW | cna-assigner |
Vendor-reported products (1)
- Cisco · Cisco Secure Firewall Threat Defense (FTD) Software
Vendor advisory
cisco-sa-ftd-snort3ssl-FBEKYXpH
Cisco Secure Firewall Threat Defense Software Snort 3 SSL Memory Management Denial of Service Vulnerability
Cisco’s rating: Medium (advisory CVSS 5.8) · Published Mar 4, 2026
Bug ID: CSCwn63410
The vendor’s rating applies to the whole advisory and can differ from this CVE’s own CVSS severity. Where this comes from