CVE-2026-49329
Openshift/oauth-server: openshift/oauth-server: quadratic-time dos via accept-language header underscore bypass on unauthenticated login endpoints
High 7.5
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.
Assigner
redhat
redhat
Published
2026-09-01
2026-09-01
Updated
2026-10-23
2026-10-23
Reserved
2026-05-29
2026-05-29
Scores
| Source | CVSS | Score | Severity | Vector |
|---|---|---|---|---|
| redhat | 3.1 | 7.5 | High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Weaknesses
Affected
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat OpenShift Container Platform 4.14 | 1791839120 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.15 | 1791598539 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.18 | 1790882323 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.19 | 1790611633 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.20 | 1790702087 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.21 | 1790707106 to < * (unaffected)
others: affected |
| Red Hat | Red Hat OpenShift Container Platform 4.22 | 1790713150 to < * (unaffected)
others: affected |
References
- 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/security/cve/CVE-2026-49329 vdb-entryx_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2483248 issue-trackingx_refsource_REDHAT
Full CVE JSON record (5.2)
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