CVE-2026-63121 (GCVE-0-2026-63121)

Vulnerability from cvelistv5 – Published: 2026-10-30 22:08 – Updated: 2026-10-30 22:08
VLAI
Title
Kubewarden trusted-repos-policy: uppercase registry host bypasses registry/image deny rules
Summary
Kubewarden policies is a collection of WebAssembly policies for securing and governing Kubernetes clusters. For versions provisionally classified as affected before 2.1.2, `trusted-repos-policy` compares an image's `registry` hostname against `reject lists` and `allow lists` case-sensitively even though `registry` DNS names are case-insensitive. An image with an uppercase or mixed-case `registry` hostname can miss a rejection rule for the equivalent lowercase host, so the admission policy accepts a resource whose container runtime pulls the same prohibited image. Only reject-list configurations have this bypass: allow-list configurations fail closed by over-denying differently cased hostnames. The security consequences depend on the configured rejection policy and deployment environment. This issue is fixed in version 2.1.2.
Severity
6.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
kubewarden policies Affected: < 2.1.2
guessed Create a notification for this product.
Show details on NVD website
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{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "policies",
          "vendor": "kubewarden",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.1.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Kubewarden policies is a collection of WebAssembly policies for securing and governing Kubernetes clusters. For versions provisionally classified as affected before 2.1.2, `trusted-repos-policy` compares an image\u0027s `registry` hostname against `reject lists` and `allow lists` case-sensitively even though `registry` DNS names are case-insensitive. An image with an uppercase or mixed-case `registry` hostname can miss a rejection rule for the equivalent lowercase host, so the admission policy accepts a resource whose container runtime pulls the same prohibited image. Only reject-list configurations have this bypass: allow-list configurations fail closed by over-denying differently cased hostnames. The security consequences depend on the configured rejection policy and deployment environment. This issue is fixed in version 2.1.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-178",
              "description": "CWE-178: Improper Handling of Case Sensitivity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-30T22:08:03.004Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/kubewarden/policies/security/advisories/GHSA-8p62-9vh2-272p",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/kubewarden/policies/security/advisories/GHSA-8p62-9vh2-272p"
        },
        {
          "name": "https://github.com/kubewarden/policies/commit/bc5597fcbbb0bc464b714ca7ff645c9743dea41b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/kubewarden/policies/commit/bc5597fcbbb0bc464b714ca7ff645c9743dea41b"
        },
        {
          "name": "https://github.com/kubewarden/policies/tree/trusted-repos-policy/v2.1.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/kubewarden/policies/tree/trusted-repos-policy/v2.1.2"
        }
      ],
      "source": {
        "advisory": "GHSA-8p62-9vh2-272p",
        "discovery": "UNKNOWN"
      },
      "title": "Kubewarden trusted-repos-policy: uppercase registry host bypasses registry/image deny rules"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-63121",
    "datePublished": "2026-10-30T22:08:03.004Z",
    "dateReserved": "2026-07-15T16:54:55.816Z",
    "dateUpdated": "2026-10-30T22:08:03.004Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-63121",
      "date": "2026-11-02",
      "epss": "0.00193",
      "percentile": "0.09"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "policies",
                "vendor": "kubewarden",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 2.1.2"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "Kubewarden policies is a collection of WebAssembly policies for securing and governing Kubernetes clusters. For versions provisionally classified as affected before 2.1.2, `trusted-repos-policy` compares an image\u0027s `registry` hostname against `reject lists` and `allow lists` case-sensitively even though `registry` DNS names are case-insensitive. An image with an uppercase or mixed-case `registry` hostname can miss a rejection rule for the equivalent lowercase host, so the admission policy accepts a resource whose container runtime pulls the same prohibited image. Only reject-list configurations have this bypass: allow-list configurations fail closed by over-denying differently cased hostnames. The security consequences depend on the configured rejection policy and deployment environment. This issue is fixed in version 2.1.2."
          }
        ],
        "id": "CVE-2026-63121",
        "lastModified": "2026-10-30T22:16:58.123",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "LOW",
                "baseScore": 6.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "REQUIRED",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 3.4,
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-10-30T22:16:58.123",
        "references": [
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/kubewarden/policies/commit/bc5597fcbbb0bc464b714ca7ff645c9743dea41b"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/kubewarden/policies/security/advisories/GHSA-8p62-9vh2-272p"
          },
          {
            "source": "security-advisories@github.com",
            "url": "https://github.com/kubewarden/policies/tree/trusted-repos-policy/v2.1.2"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-178"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}



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