CVE-2026-6245: fedoraproject sssd

Vulnerability summary

CVE-2026-6245 is a medium (CVSS 5.5) vulnerability in fedoraproject sssd. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.7% of scored vulnerabilities.

Timeline

1. 15-04-2026
   PublishedVulnerability first disclosed.
2. 01-09-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in the System Security Services Daemon (SSSD). The pam_passkey_child_read_data() function within the PAM passkey responder fails to properly handle raw bytes received from a pipe. Because the data is treated as a NUL-terminated C string without explicit termination, it results in an out-of-bounds read when processed by functions like snprintf(). A local attacker could potentially trigger this vulnerability by initiating a crafted passkey authentication request, causing the SSSD PAM responder to crash, resulting in a local Denial of Service (DoS).

• CWE-805Buffer Access with Incorrect Length ValueThe product uses a sequential operation to read or write a buffer, but it uses an incorrect length value that causes it to access memory that is outside of the bounds of the buffer.