---
id: CVE-2026-104039
title: >-
  Sssd: sssd: denial of service via stale connection state reuse in pam gssapi
  responder
summary: >-
  A flaw was found in SSSD. A local user can cause a denial of service (DoS) by
  disrupting system authentication services. When handling Generic Security
  Services Application Programming Interface (GSSAPI) authentication in the
  Pluggable A…
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-825
vendor: Red Hat
product: sssd
affected:
  - sssd (all versions)
  - sssd
  - sssd (all versions)
  - sssd (all versions)
  - sssd (all versions)
  - openshift/ose-rhel-coreos-8 (all versions)
  - openshift/ose-rhel-coreos-9 (all versions)
published: '2026-10-06'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T01:00:41.199Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-104039'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-104039'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2478956'
    label: RHBZ#2478956
tags:
  - cve.org
ingestedAt: '2026-10-06T01:38:44.804Z'
---

## Overview

A flaw was found in SSSD. A local user can cause a denial of service (DoS) by disrupting system authentication services. When handling Generic Security Services Application Programming Interface (GSSAPI) authentication in the Pluggable Authentication Module (PAM) responder, cached connection state is freed upon completion without clearing the reference pointer. An attacker can exploit this by sending an additional request over the same connection, causing the service to access invalid memory and unexpectedly terminate.

## Affected

- `sssd (all versions)`
- `sssd`
- `sssd (all versions)`
- `sssd (all versions)`
- `sssd (all versions)`
- `openshift/ose-rhel-coreos-8 (all versions)`
- `openshift/ose-rhel-coreos-9 (all versions)`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.