CVE-2026-49329 (GCVE-0-2026-49329)

Vulnerability from cvelistv5 – Published: 2026-09-01 15:30 – Updated: 2026-10-30 04:24
VLAI
Title
Openshift/oauth-server: openshift/oauth-server: quadratic-time dos via accept-language header underscore bypass on unauthenticated login endpoints
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-2022-32149 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.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-01 17:05 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1072 records in the last 180 days details
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:74380 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:74383 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:74429 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:74434 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:79039 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:82785 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:82813 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:89715 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-49329 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2483248 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat OpenShift Container Platform 4.14 Unaffected: 1791839120 , < * (rpm)
    cpe:/a:redhat:openshift:4.14::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.15 Unaffected: 1791598539 , < * (rpm)
    cpe:/a:redhat:openshift:4.15::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.16 Unaffected: 1792883889 , < * (rpm)
    cpe:/a:redhat:openshift:4.16::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.18 Unaffected: 1790882323 , < * (rpm)
    cpe:/a:redhat:openshift:4.18::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.19 Unaffected: 1790611633 , < * (rpm)
    cpe:/a:redhat:openshift:4.19::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.20 Unaffected: 1790702087 , < * (rpm)
    cpe:/a:redhat:openshift:4.20::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.21 Unaffected: 1790707106 , < * (rpm)
    cpe:/a:redhat:openshift:4.21::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4.22 Unaffected: 1790713150 , < * (rpm)
    cpe:/a:redhat:openshift:4.22::el9
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 5     cpe:/a:redhat:openshift:5
Create a notification for this product.
Date Public
2026-08-31 20:00
Show details on NVD website

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}



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