---
id: CVE-2026-104039
title: A flaw was found in SSSD
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'
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: '2026-10-08'
sourceUpdated: '2026-10-08T03:16:33.053'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-104039'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-104039'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2478956'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-104039.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-104039'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-104039'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-08T02:39:57.403101Z'
epss: 0.00102
epssPercentile: 0.00919
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.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-104039.json)