---
id: CVE-2026-49329
title: A flaw was found in openshift/oauth-server
summary: >-
  A flaw was found in openshift/oauth-server. The OAuth login and error page
  endpoints pass the unauthenticated Accept-Language header to
  golang.org/x/text/language.ParseAcceptLanguage() without input validation. A
  bypass of the CVE-2022-3…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-407
vendor: Red Hat
product: openshift4/ose-oauth-server-rhel9
affected:
  - openshift4/ose-oauth-server-rhel9 (all versions)
  - openshift4/ose-oauth-server-rhel9 (all versions)
  - openshift4/ose-oauth-server-rhel9 (all versions)
  - openshift4/ose-oauth-server-rhel9 (all versions)
  - openshift4/ose-oauth-server-rhel8 (all versions)
patched:
  - openshift_container_platform 4.20
  - openshift_container_platform 4.21
  - openshift_container_platform 4.22
published: '2026-09-01'
updated: '2026-10-07'
sourceUpdated: '2026-10-07T15:17:21.373'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-49329'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:74380'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:74383'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:74429'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:74434'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-49329'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2483248'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-49329.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-49329'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-49329'
  - url: 'https://access.redhat.com/errata/RHSA-2026:79039'
    label: 'RHSA-2026:79039'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82785'
    label: 'RHSA-2026:82785'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82813'
    label: 'RHSA-2026:82813'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-01T17:05:19.987171Z'
epss: 0.00705
epssPercentile: 0.53137
ingestedAt: '2026-09-18T13:41:41.660Z'
---

## Overview

A flaw was found in openshift/oauth-server. The OAuth login and error page endpoints pass the unauthenticated Accept-Language header to golang.org/x/text/language.ParseAcceptLanguage() without input validation. A bypass of the CVE-2022-32149 mitigation exists: the upstream guard counts only '-' characters but the internal BCP 47 scanner aliases '_' to '-' after the guard check. An unauthenticated attacker can send a crafted Accept-Language header using '_' separators to trigger quadratic-time parsing, consuming excessive CPU and denying authentication to all cluster users.

## Remediation

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

## Vendor advisories

- **RHSA-2026:74380** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.20 · released 2026-10-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:74380)
- **RHSA-2026:74383** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.21 · released 2026-10-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:74383)
- **RHSA-2026:74429** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.22 · released 2026-10-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:74429)
- **Red Hat VEX** · Important · affected: Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat OpenShift Container Platform 4 · updated 2026-10-09 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-49329.json)
- **RHSA-2026:74434** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.19 · released 2026-10-07 · [advisory](https://access.redhat.com/errata/RHSA-2026:74434)