Vulnerability-Lookup

GHSA-2MR2-J2WM-V93X

Vulnerability from github – Published: 2026-09-01 18:30 – Updated: 2026-09-01 18:30

Details

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.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-49329"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-407"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-01T16:16:57Z",
    "severity": "HIGH"
  },
  "details": "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 \u0027-\u0027 characters but the internal BCP 47 scanner aliases \u0027_\u0027 to \u0027-\u0027 after the guard check. An unauthenticated attacker can send a crafted Accept-Language header using \u0027_\u0027 separators to trigger quadratic-time parsing, consuming excessive CPU and denying authentication to all cluster users.",
  "id": "GHSA-2mr2-j2wm-v93x",
  "modified": "2026-09-01T18:30:40Z",
  "published": "2026-09-01T18:30:40Z",
  "references": [
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      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49329"
    },
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      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-49329"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2483248"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-09-01 15:30 – Updated: 2026-09-01 17:05

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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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 redhat root

References

2 references

URL	Tags
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

1 product

Vendor	Product	Version
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public

2026-08-31 20:00

Credits

Red Hat would like to thank tonghuaroot for reporting this issue.

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                  },
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-2MR2-J2WM-V93X

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

Tags

Sightings

Nomenclature