CVE-2026-49329
Openshift/oauth-server: openshift/oauth-server: quadratic-time dos via accept-language header underscore bypass on unauthenticated login endpoints
- State
- Published
- Severity
- 7.5 High
- Published
- Sep 1, 2026
- Updated
- Oct 30, 2026
- Reserved
- May 29, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | redhat |
Weaknesses
- CWE-407 Inefficient Algorithmic Complexity
Affected Products
| Product | Versions |
|---|---|
Red Hat OpenShift Container Platform 4.14Red Hat |
|
Red Hat OpenShift Container Platform 4.15Red Hat |
|
Red Hat OpenShift Container Platform 4.16Red Hat |
|
Red Hat OpenShift Container Platform 4.18Red Hat |
|
Red Hat OpenShift Container Platform 4.19Red Hat |
|
Red Hat OpenShift Container Platform 4.20Red Hat |
|
Red Hat OpenShift Container Platform 4.21Red Hat |
|
Red Hat OpenShift Container Platform 4.22Red Hat |
|
Red Hat OpenShift Container Platform 5Red Hat |
References
- RHSA-2026:74380vendor-advisory
- RHSA-2026:74383vendor-advisory
- RHSA-2026:74429vendor-advisory
- RHSA-2026:74434vendor-advisory
- RHSA-2026:79039vendor-advisory
- RHSA-2026:82785vendor-advisory
- RHSA-2026:82813vendor-advisory
- RHSA-2026:89715vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-49329vdb-entry
- RHBZ#2483248issue-tracking
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