---
title: "CVE-2026-87853: SSSD - Authentication Bypass"
description: "SSSD contains an authentication bypass caused by prefix comparison of OIDC subject identifiers in eval_access_token_buf(), letting attackers authenticate as other users with prefix IdP identifiers, exploit requires attacker to control IdP identifier."
url: https://panop.io/threat-heartbeat/CVE-2026-87853/
---

# CVE-2026-87853 SSSD - Authentication Bypass

SSSD contains an authentication bypass caused by prefix comparison of OIDC subject identifiers in eval\_access\_token\_buf(), letting attackers authenticate as other users with prefix IdP identifiers, exploit requires attacker to control IdP identifier.

CVSS base score 7.5 /10

High

CISA KEV

Not listed

Public exploit

None known

EPSS

0.33% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-87853)

## Details

Type

Authentication Bypass

Impact

Broken Authentication

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Published

9 September 2026

Updated

15 October 2026

Weakness

[CWE-187](https://cwe.mitre.org/data/definitions/187.html)

## Vendor fix

Update to the latest version with fixed exact matching of OIDC subject identifiers.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-87853](https://nvd.nist.gov/vuln/detail/CVE-2026-87853)
- [https://access.redhat.com/security/cve/CVE-2026-87853](https://access.redhat.com/security/cve/CVE-2026-87853)
- [https://bugzilla.redhat.com/show\_bug.cgi?id=2530888](https://bugzilla.redhat.com/show_bug.cgi?id=2530888)
- [https://access.redhat.com/errata/RHSA-2026:77534](https://access.redhat.com/errata/RHSA-2026:77534)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)