FKIE_CVE-2026-49478

Vulnerability from fkie_nvd - Published: 2026-08-13 13:19 - Updated: 2026-08-13 13:19
Severity
8.7 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Summary
Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Versions through 1.8.5 improperly follow cross-host redirects and attach Kubernetes ServiceAccount tokens during OIDC discovery, allowing a malicious or compromised issuer to perform blind SSRF, substitute and cache malicious JWKS keys, or disclose ServiceAccount tokens to external hosts. Version 1.8.6 blocks cross-host redirects, restricts token injection, and restricts local token loading. No known workarounds are available.
References
security-advisories@github.comhttps://github.com/sigstore/fulcio/commit/378c654f48c3bafdced04ead7010aab2cb4c6ca1
security-advisories@github.comhttps://github.com/sigstore/fulcio/pull/2354
security-advisories@github.comhttps://github.com/sigstore/fulcio/releases/tag/v1.8.6
security-advisories@github.comhttps://github.com/sigstore/fulcio/security/advisories/GHSA-f5mr-q85p-6hh6
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "fulcio",
          "vendor": "sigstore",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.8.6"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Versions through 1.8.5 improperly follow cross-host redirects and attach Kubernetes ServiceAccount tokens during OIDC discovery, allowing a malicious or compromised issuer to perform blind SSRF, substitute and cache malicious JWKS keys, or disclose ServiceAccount tokens to external hosts. Version 1.8.6 blocks cross-host redirects, restricts token injection, and restricts local token loading. No known workarounds are available."
    }
  ],
  "id": "CVE-2026-49478",
  "lastModified": "2026-08-13T13:19:09.790",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.8,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-13T13:19:09.790",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sigstore/fulcio/commit/378c654f48c3bafdced04ead7010aab2cb4c6ca1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sigstore/fulcio/pull/2354"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sigstore/fulcio/releases/tag/v1.8.6"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/sigstore/fulcio/security/advisories/GHSA-f5mr-q85p-6hh6"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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