CVE-2026-88252 Sssd: sssd: denial of service via responder connection retry loop during file descriptor exhaustion

Description

A flaw was found in sssd. A local user can cause a Denial of Service (DoS) by exhausting the responder service's available file descriptors (system handles used for open connections). By opening and maintaining many concurrent connections to a responder socket while continuing to queue new connection attempts, an attacker can trigger an unthrottled retry loop. This condition leads to high CPU utilization and stalls the service, preventing legitimate identity and authentication requests from being processed.

Exploitable with local access to the machine, with an ordinary account and without any user action; an attacker can seriously compromise confidentiality, integrity or availability.

Attack vector

Local

Attack complexity

High

Privileges required

Low

Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected products and versions