{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-53939",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-11T15:46:12.318Z",
        "datePublished": "2026-09-08T23:36:13.668Z",
        "dateUpdated": "2026-09-09T15:12:15.459Z"
    },
    "containers": {
        "cna": {
            "title": "OpenIDC/cjose uses all-zero Content Encryption Key for AES-CBC-HMAC JWE encryption",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-321",
                            "lang": "en",
                            "description": "CWE-321: Use of Hard-coded Cryptographic Key",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-330",
                            "lang": "en",
                            "description": "CWE-330: Use of Insufficiently Random Values",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 9.1,
                        "baseSeverity": "CRITICAL",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/OpenIDC/cjose/security/advisories/GHSA-f6wf-pqg3-6wqq",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/OpenIDC/cjose/security/advisories/GHSA-f6wf-pqg3-6wqq"
                },
                {
                    "name": "https://github.com/OpenIDC/cjose/commit/2a6e5bd969fa20059fb00913fb9f57d77ea6a4d9",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/OpenIDC/cjose/commit/2a6e5bd969fa20059fb00913fb9f57d77ea6a4d9"
                },
                {
                    "name": "https://github.com/OpenIDC/cjose/releases/tag/v0.6.2.6",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/OpenIDC/cjose/releases/tag/v0.6.2.6"
                }
            ],
            "affected": [
                {
                    "vendor": "OpenIDC",
                    "product": "cjose",
                    "versions": [
                        {
                            "version": ">= 0.6.1, < 0.6.2.6",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-09-08T23:36:13.668Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). In versions 0.6.1 through 0.6.2.5, when cjose encrypts a JWE using an AES-CBC-HMAC content-encryption algorithm (`A128CBC-HS256`, `A192CBC-HS384`, or `A256CBC-HS512`) together with any key-management algorithm that generates a fresh content-encryption key (CEK), the CEK is all zero bytes instead of being randomly generated. The resulting JWE is therefore encrypted and authenticated under a fixed, publicly known key, so anyone who obtains the JWE can recover the plaintext and forge or modify the content. This is fixed in version 0.6.2.6 by `_cjose_jwe_set_cek_aes_cbc()` generating the CEK from `RAND_bytes`. A regression test asserts that the `encrypted_key` differs across two encryptions for each AES-CBC-HMAC variant. Until upgrading, for data encrypted with cjose, three options are available. Use an AES-GCM `enc` (`A128GCM` / `A192GCM` / `A256GCM`) instead of an AES-CBC-HMAC `enc`,  use `alg=dir` with a caller-supplied CEK, or avoid using cjose for JWE encryption with the affected algorithm pair. These are mitigations for new ciphertexts only; data already encrypted under the zero key remains compromised and should be re-encrypted (and any secrets it contained rotated)."
                }
            ],
            "source": {
                "advisory": "GHSA-f6wf-pqg3-6wqq",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/OpenIDC/cjose/security/advisories/GHSA-f6wf-pqg3-6wqq",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-09-09T15:12:10.094529Z",
                                "id": "CVE-2026-53939",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-09-09T15:12:15.459Z"
                }
            }
        ]
    }
}