Vulnerability-Lookup

GHSA-4G2F-XCPH-2335

Vulnerability from github – Published: 2026-02-04 00:30 – Updated: 2026-02-04 00:30

Details

A security issue was discovered in ingress-nginx where the protection afforded by the auth-url Ingress annotation may not be effective in the presence of a specific misconfiguration.

If the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the auth-url annotation may be accessed even when authentication fails.

Note that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.

Severity ?

3.1 (Low)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-24513"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-754"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-03T23:16:07Z",
    "severity": "LOW"
  },
  "details": "A security issue was discovered in ingress-nginx\u00a0where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration.\n\nIf the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails.\n\nNote that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.",
  "id": "GHSA-4g2f-xcph-2335",
  "modified": "2026-02-04T00:30:29Z",
  "published": "2026-02-04T00:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24513"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kubernetes/kubernetes/issues/136679"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-24513 (GCVE-0-2026-24513)

Vulnerability from cvelistv5 – Published: 2026-02-03 22:17 – Updated: 2026-02-03 22:17

Title

ingress-nginx auth-url protection bypass

Summary

A security issue was discovered in ingress-nginx where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration. If the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails. Note that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component.

Severity ?

3.1 (Low)


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

CWE

CWE-754 - Improper Check for Unusual or Exceptional Conditions

Assigner

kubernetes

References

URL

Tags

https://github.com/kubernetes/kubernetes/issues/136679

Impacted products

	Vendor	Product	Version
	Kubernetes	ingress-nginx	Affected: 0 , < 1.13.7 (semver) Affected: 0 , < 1.14.2 (semver)

Show details on NVD website

JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "ingress-nginx",
          "repo": "https://github.com/kubernetes/ingress-nginx",
          "vendor": "Kubernetes",
          "versions": [
            {
              "lessThan": "1.13.7",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.14.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "datePublic": "2026-02-02T14:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "A security issue was discovered in ingress-nginx where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration.\u003cbr\u003eIf the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails.\u003cbr\u003eNote that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component."
            }
          ],
          "value": "A security issue was discovered in ingress-nginx\u00a0where the protection afforded by the `auth-url` Ingress annotation may not be effective in the presence of a specific misconfiguration.\n\nIf the ingress-nginx controller is configured with a default custom-errors configuration that includes HTTP errors 401 or 403, and if the configured default custom-errors backend is defective and fails to respect the X-Code HTTP header, then an Ingress with the `auth-url` annotation may be accessed even when authentication fails.\n\nNote that the built-in custom-errors backend works correctly. To trigger this issue requires an administrator to specifically configure ingress-nginx with a broken external component."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-115",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-115 Authentication Bypass"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.1,
            "baseSeverity": "LOW",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-754",
              "description": "CWE-754 Improper Check for Unusual or Exceptional Conditions",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-03T22:17:17.315Z",
        "orgId": "a6081bf6-c852-4425-ad4f-a67919267565",
        "shortName": "kubernetes"
      },
      "references": [
        {
          "url": "https://github.com/kubernetes/kubernetes/issues/136679"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "ingress-nginx auth-url protection bypass",
      "x_generator": {
        "engine": "Vulnogram 0.5.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a6081bf6-c852-4425-ad4f-a67919267565",
    "assignerShortName": "kubernetes",
    "cveId": "CVE-2026-24513",
    "datePublished": "2026-02-03T22:17:17.315Z",
    "dateReserved": "2026-01-23T06:54:35.913Z",
    "dateUpdated": "2026-02-03T22:17:17.315Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-4G2F-XCPH-2335

CVE-2026-24513 (GCVE-0-2026-24513)

Tags

Sightings

Nomenclature