CVE-2026-20135 (GCVE-0-2026-20135)
Vulnerability from cvelistv5
Published
2026-09-16 20:12
Modified
2026-09-17 13:40
Severity ?
8.6 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CWE
Summary
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.
References
Impacted products
Vendor Product Version
Cisco Cisco Secure Firewall Threat Defense (FTD) Software Version: 7.0.0
Version: 7.0.0.1
Version: 7.0.1
Version: 7.0.1.1
Version: 7.0.2
Version: 7.2.0
Version: 7.0.2.1
Version: 7.0.3
Version: 7.2.0.1
Version: 7.0.4
Version: 7.2.1
Version: 7.0.5
Version: 7.3.0
Version: 7.2.2
Version: 7.2.3
Version: 7.3.1
Version: 7.2.4
Version: 7.0.6
Version: 7.2.5
Version: 7.2.4.1
Version: 7.3.1.1
Version: 7.4.0
Version: 7.0.6.1
Version: 7.2.5.1
Version: 7.4.1
Version: 7.2.6
Version: 7.0.6.2
Version: 7.4.1.1
Version: 7.2.7
Version: 7.2.5.2
Version: 7.3.1.2
Version: 7.2.8
Version: 7.6.0
Version: 7.4.2
Version: 7.2.8.1
Version: 7.0.6.3
Version: 7.4.2.1
Version: 7.2.9
Version: 7.0.7
Version: 7.7.0
Version: 7.4.2.2
Version: 7.2.10
Version: 7.6.1
Version: 7.4.2.3
Version: 7.0.8
Version: 7.6.2
Version: 7.7.10
Version: 7.7.11
Version: 7.0.8.1
Version: 7.6.2.1
Version: 7.7.10.1
Version: 7.4.2.4
Version: 7.2.10.2
Version: 7.4.3
Version: 7.6.4
Version: 7.4.4
Version: 7.0.9
Version: 7.2.11
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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. 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