---
id: CVE-2026-97791
title: >-
  In Apache CXF, STSTokenValidator checks whether a SAML assertion is signed by
  a trusted certificate before deciding to send it to the STS
summary: >-
  In Apache CXF, STSTokenValidator checks whether a SAML assertion is signed by
  a trusted certificate before deciding to send it to the STS. That result was
  stored in one object shared by all requests, so one request could read
  another's r…
severity: none
published: '2026-10-09'
updated: '2026-10-09'
sourceUpdated: '2026-10-09T16:33:39.007'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97791'
references:
  - url: 'https://lists.apache.org/thread.html/ssdr417qgms9fjl0m8802xd8170wnk1l'
    label: security@apache.org
  - url: 'http://www.openwall.com/lists/oss-security/2026/10/09/10'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
ingestedAt: '2026-10-09T12:53:29.302Z'
---

## Overview

In Apache CXF, STSTokenValidator checks whether a SAML assertion is signed by a trusted certificate before deciding to send it to the STS. That result was stored in one object shared by all requests, so one request could read another's result. A remote, unauthenticated attacker could send a forged assertion signed with an untrusted certificate while legitimate requests were being processed, and it could be accepted as trusted without ever reaching the STS. Only services that use STSTokenValidator to validate SAML tokens without alwaysValidateToSts set are affected. 
Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.

## Remediation

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