{
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    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-42791",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-27T15:40:27.647844Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-27T15:40:49.123Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unknown",
          "modules": [
            "pubkey_ocsp"
          ],
          "packageName": "public_key",
          "packageURL": "pkg:otp/public_key?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp\u0026vcs_url=git%20https:%2F%2Fgithub.com%2Ferlang%2Fotp.git",
          "product": "OTP",
          "programFiles": [
            "src/pubkey_ocsp.erl"
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          "programRoutines": [
            {
              "name": "pubkey_ocsp:verify_response/5"
            },
            {
              "name": "pubkey_ocsp:is_authorized_responder/3"
            }
          ],
          "repo": "https://github.com/erlang/otp",
          "vendor": "Erlang",
          "versions": [
            {
              "changes": [
                {
                  "at": "1.17.1.3",
                  "status": "unaffected"
                },
                {
                  "at": "1.20.3.1",
                  "status": "unaffected"
                },
                {
                  "at": "1.21.1",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "1.16",
              "versionType": "otp"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unknown",
          "modules": [
            "pubkey_ocsp"
          ],
          "packageName": "erlang/otp",
          "packageURL": "pkg:github/erlang/otp",
          "product": "OTP",
          "programFiles": [
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          "programRoutines": [
            {
              "name": "pubkey_ocsp:verify_response/5"
            },
            {
              "name": "pubkey_ocsp:is_authorized_responder/3"
            }
          ],
          "repo": "https://github.com/erlang/otp",
          "vendor": "Erlang",
          "versions": [
            {
              "changes": [
                {
                  "at": "27.3.4.12",
                  "status": "unaffected"
                },
                {
                  "at": "28.5.0.1",
                  "status": "unaffected"
                },
                {
                  "at": "29.0.1",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "27.0",
              "versionType": "otp"
            },
            {
              "changes": [
                {
                  "at": "7995f1fdaee3da569bb810358ce0f546471d169b",
                  "status": "unaffected"
                },
                {
                  "at": "b3870e02405c709a872b01ba6086065620cdfe76",
                  "status": "unaffected"
                }
              ],
              "lessThan": "*",
              "status": "affected",
              "version": "2b1a742c651b90f8a7a1fb2ddde73f29915ea376",
              "versionType": "git"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "For the \u003ctt\u003essl\u003c/tt\u003e application, OCSP stapling must be enabled by setting the \u003ctt\u003estapling\u003c/tt\u003e option to \u003ctt\u003estaple\u003c/tt\u003e in the TLS client options. OCSP stapling is not enabled by default.\u003cp\u003eApplications calling \u003ctt\u003epublic_key:pkix_ocsp_validate/5\u003c/tt\u003e directly are unconditionally affected when that function is used.\u003c/p\u003e"
            }
          ],
          "value": "For the ssl application, OCSP stapling must be enabled by setting the stapling option to staple in the TLS client options. OCSP stapling is not enabled by default.\n\nApplications calling public_key:pkix_ocsp_validate/5 directly are unconditionally affected when that function is used."
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
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                  "criteria": "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "27.3.4.12",
                  "versionStartIncluding": "27.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "28.5.0.1",
                  "versionStartIncluding": "28.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "29.0.1",
                  "versionStartIncluding": "29.0",
                  "vulnerable": true
                }
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              "negate": false,
              "operator": "OR"
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          ],
          "operator": "AND"
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      ],
      "credits": [
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Jakub Witczak"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Ingela Anderton Andin"
        }
      ],
      "descriptions": [
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          "lang": "en",
          "supportingMedia": [
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              "base64": false,
              "type": "text/html",
              "value": "Improper Certificate Validation vulnerability in Erlang OTP \u003ctt\u003epublic_key\u003c/tt\u003e (\u003ctt\u003epubkey_ocsp\u003c/tt\u003e module) allows forged OCSP responses signed with an expired responder certificate to be accepted as valid.\u003cp\u003eOCSP response verification in \u003ctt\u003epubkey_ocsp:verify_response/5\u003c/tt\u003e and \u003ctt\u003epubkey_ocsp:is_authorized_responder/3\u003c/tt\u003e in \u003ctt\u003elib/public_key/src/pubkey_ocsp.erl\u003c/tt\u003e does not check the validity period (\u003ctt\u003enotBefore\u003c/tt\u003e/\u003ctt\u003enotAfter\u003c/tt\u003e) of the OCSP responder certificate. An attacker who has obtained the private key of an expired CA-designated OCSP responder certificate can forge OCSP responses that Erlang/OTP accepts as valid.\u003c/p\u003e\u003cp\u003eThis affects TLS clients using OCSP stapling via the \u003ctt\u003essl\u003c/tt\u003e application: a malicious or compromised server can present a revoked TLS certificate together with a forged OCSP response signed by an expired responder key, and the client will accept the revoked certificate as valid. It also affects applications calling \u003ctt\u003epublic_key:pkix_ocsp_validate/5\u003c/tt\u003e directly, where the impact depends on the use case \u2014 server-side client certificate validation using this API may allow authentication bypass with a revoked client certificate.\u003c/p\u003e\u003cp\u003eThis issue affects OTP from OTP 27.0 before OTP\u0026nbsp;29.0.1, OTP\u0026nbsp;28.5.0.1 and OTP\u0026nbsp;27.3.4.12, corresponding to \u003ctt\u003epublic_key\u003c/tt\u003e from 1.16 before 1.21.1, 1.20.3.1 and 1.17.1.3.\u003c/p\u003e"
            }
          ],
          "value": "Improper Certificate Validation vulnerability in Erlang OTP public_key (pubkey_ocsp module) allows forged OCSP responses signed with an expired responder certificate to be accepted as valid.\n\nOCSP response verification in pubkey_ocsp:verify_response/5 and pubkey_ocsp:is_authorized_responder/3 in lib/public_key/src/pubkey_ocsp.erl does not check the validity period (notBefore/notAfter) of the OCSP responder certificate. An attacker who has obtained the private key of an expired CA-designated OCSP responder certificate can forge OCSP responses that Erlang/OTP accepts as valid.\n\nThis affects TLS clients using OCSP stapling via the ssl application: a malicious or compromised server can present a revoked TLS certificate together with a forged OCSP response signed by an expired responder key, and the client will accept the revoked certificate as valid. It also affects applications calling public_key:pkix_ocsp_validate/5 directly, where the impact depends on the use case \u2014 server-side client certificate validation using this API may allow authentication bypass with a revoked client certificate.\n\nThis issue affects OTP from OTP 27.0 before OTP\u00a029.0.1, OTP\u00a028.5.0.1 and OTP\u00a027.3.4.12, corresponding to public_key from 1.16 before 1.21.1, 1.20.3.1 and 1.17.1.3."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-475",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-475 Signature Spoofing by Improper Validation"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-295",
              "description": "CWE-295 Improper Certificate Validation",
              "lang": "en",
              "type": "CWE"
            },
            {
              "cweId": "CWE-672",
              "description": "CWE-672 Operation on a Resource after Expiration or Release",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-24T14:14:24.911Z",
        "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "shortName": "EEF"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory",
            "related"
          ],
          "url": "https://github.com/erlang/otp/security/advisories/GHSA-cjxj-wj6x-3fff"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://cna.erlef.org/cves/CVE-2026-42791.html"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://osv.dev/vulnerability/EEF-CVE-2026-42791"
        },
        {
          "tags": [
            "x_version-scheme"
          ],
          "url": "https://www.erlang.org/doc/system/versions.html#order-of-versions"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/erlang/otp/commit/7995f1fdaee3da569bb810358ce0f546471d169b"
        },
        {
          "tags": [
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          ],
          "url": "https://github.com/erlang/otp/commit/b3870e02405c709a872b01ba6086065620cdfe76"
        }
      ],
      "source": {
        "discovery": "INTERNAL"
      },
      "title": "OCSP responder certificate validity period not checked in public_key",
      "workarounds": [
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              "value": "\u003cul\u003e\u003cli\u003eFor TLS clients using the \u003ctt\u003essl\u003c/tt\u003e application, disable OCSP stapling by setting \u003ctt\u003e{stapling, no_staple}\u003c/tt\u003e in the client options, or switch to CRL-based revocation checking with \u003ctt\u003e{crl_check, true}\u003c/tt\u003e.\u003c/li\u003e\u003cli\u003eFor applications calling \u003ctt\u003epublic_key:pkix_ocsp_validate/5\u003c/tt\u003e directly, validate the responder certificate\u0027s validity period in application code before calling the function.\u003c/li\u003e\u003c/ul\u003e"
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          ],
          "value": "* For TLS clients using the ssl application, disable OCSP stapling by setting {stapling, no_staple} in the client options, or switch to CRL-based revocation checking with {crl_check, true}.\n* For applications calling public_key:pkix_ocsp_validate/5 directly, validate the responder certificate\u0027s validity period in application code before calling the function."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
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    }
  },
  "cveMetadata": {
    "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
    "assignerShortName": "EEF",
    "cveId": "CVE-2026-42791",
    "datePublished": "2026-05-27T12:23:13.584Z",
    "dateReserved": "2026-04-29T18:06:33.251Z",
    "dateUpdated": "2026-07-24T14:14:24.911Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}