CVE-2026-20050
MediumCVSS 6.8Exploitation Probability (EPSS)
Low risk31th percentile - higher than 31% of all known CVEs
Summary
A vulnerability in the Do Not Decrypt exclusion feature of the SSL decryption feature of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The issue is due to improper memory management during inspection of TLS 1.2 encrypted traffic.
Risk Assessment
An attacker could send crafted TLS 1.2 traffic, causing a device reload and leading to network service disruption.
Recommendation
Apply Cisco updates for FTD. Limit exposure to TLS 1.2 traffic if possible until patches are deployed.
Other vulnerabilities in Cisco Secure Firewall Threat Defense (FTD) Software
Original NVD description (English source)
A vulnerability in the Do Not Decrypt exclusion feature of the SSL decryption feature of Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper memory management during the inspection of TLS 1.2 encrypted traffic. An attacker could exploit this vulnerability by sending crafted TLS 1.2 encrypted traffic through an affected device. A successful exploit could allow the attacker to cause a reload of an affected device. Note: This vulnerability only affects traffic that is encrypted by TLS 1.2. Other versions of TLS are not affected.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS