CVE-2026-20135
CVE CVE-2026-20135EUVD EUVD-2026-81123Published 2026-09-16T20:12:09.000ZLast changed 2026-09-17T13:40:57.000ZCVSS 8.6
What the advisory describes
A vulnerability in the TLS 1.3 implementation in Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper buffer management during the TLS 1.3 connection. An attacker could exploit this vulnerability by sending a crafted TLS 1.3 packet to an affected system through a TLS 1.3-enabled listening socket. A successful exploit could allow the attacker to cause the LINA process to crash, which would cause the device to reload. The reload can happen before or after authentication of the connection.Note: TLS 1.3 connections include both data traffic and user-management traffic.
Source: EUVD (ENISA), in the words of the advisory.
Products the advisory names
These come from the advisory itself, not from any check we performed.
- Cisco — Cisco Secure Firewall Threat Defense (FTD) Software 7.0.0; 7.2.10.2; 7.0.6; 7.2.10; 7.4.2.4; 7.2.6; 7.4.0; 7.0.9; 7.7.10.1; 7.0.7; 7.3.1; 7.4.1.1; 7.3.0; 7.6.2.1; 7.0.0.1; 7.2.4.1; 7.6.2; 7.2.5.2; 7.2.7; 7.2.4; 7.2.0.1; 7.4.2.3; 7.0.6.3; 7.0.3; 7.3.1.2; 7.4.4; 7.0.1; 7.6.4; 7.4.3; 7.4.1; 7.2.9; 7.0.5; 7.4.2.2; 7.0.2.1; 7.0.8; 7.6.1; 7.2.2; 7.2.5; 7.7.0; 7.7.11; 7.0.1.1; 7.4.2; 7.2.11; 7.2.8; 7.0.8.1; 7.0.4; 7.0.2; 7.6.0; 7.0.6.2; 7.4.2.1; 7.7.10; 7.3.1.1; 7.2.5.1; 7.2.0; 7.2.8.1; 7.0.6.1; 7.2.1; 7.2.3
The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.
Carried in the product catalogue
An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.
- Cisco — Secure Firewall Threat Defense (FTD) Software
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