CVE-2026-6245

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).

This Moderate impact flaw in the System Security Services Daemon (SSSD) can lead to a local Denial of Service. A local attacker can exploit an out-of-bounds read in the PAM passkey responder by sending a crafted authentication request, causing the SSSD service to crash. This affects Red Hat systems where SSSD is configured and local user access is possible.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.