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.
References10
- access.redhat.com/errata/RHSA-2026:74380
- access.redhat.com/errata/RHSA-2026:74383
- access.redhat.com/errata/RHSA-2026:74429
- access.redhat.com/errata/RHSA-2026:74434
- access.redhat.com/errata/RHSA-2026:79039
- access.redhat.com/errata/RHSA-2026:82785
- access.redhat.com/errata/RHSA-2026:82813
- access.redhat.com/errata/RHSA-2026:89715
- access.redhat.com/security/cve/CVE-2026-49329
- bugzilla.redhat.com/show_bug.cgi?id=2483248
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 54 · as of 8 November 2026
- CWE
- CWE-407
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.