Medium severity · published Mar 4, 2026
CVE-2026-20050
Cisco Secure Firewall Threat Defense Decryption Policy Denial of Service Vulnerability
6.8
CVSS
0.4%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CS
Cisco Secure Firewall Threat Defense (FTD) Software · Cisco
7.0.0; 7.0.0.1; 7.0.1; 7.1.0; 7.0.1.1; 7.1.0.1; +34 more · source: vendor
SF
Secure Firewall Threat Defense · Cisco
7.1.0 before 7.2.11; 7.3.0 before 7.4.4; 7.6.0 before 7.6.4; 7.7.0 before 7.7.11 · source: NVD
Affected product
CS
Cisco Secure Firewall Threat Defense (FTD) Software
Cisco
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