FKIE_CVE-2026-63072

Vulnerability from fkie_nvd - Published: 2026-08-25 13:19 - Updated: 2026-08-25 15:16
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports, causing an 8-byte out-of-bounds heap write. Impact summary: An attacker who supplies a crafted CMS message can trigger a deterministic 8-byte out-of-bounds heap write when the victim decrypts it with CMS_decrypt(), corrupting the heap and typically resulting in a Denial of Service. CWE: CWE-787: Out-of-bounds Write Description: The key-wrap OID is potentially attacker-controlled on the wire. CMS unwrapping allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers. An attacker can take a legitimate message and change a single OID byte to select the padded variant while leaving the message otherwise valid. Since the unwrap key is derived from the recipient's private operation (ECDH key agreement or ML-KEM decapsulation), the RFC 5649 integrity check cannot pass, and the decryption fails with integrity failure. The write is a fixed-size (8-byte), fixed-value (zero) heap overflow immediately past the allocation, requires no special configuration, and is reachable from the public CMS_decrypt() function. The consequence is a heap corruption leading to a Denial of Service. The fix in the CMS code sizes the unwrap output buffer for the worst case so a failed unwrap cannot write past the allocation. FIPS impact: no As the CMS code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
References
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/2a3dac874c8057c1f0186849bf1ede1ae7b6b756
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/87784ad619af36b8807c2044b3940006fccc1e42
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/9530a5fd1aacaeccdced4478ea2340a480613335
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/9ec2f6d2ae2bcad907cf7ee38584855bafe4979a
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/a0c8ec557d9cac078f032d76cdf684fe743eb382
openssl-security@openssl.orghttps://openssl-library.org/news/secadv/20260825.txt
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "4.0.2",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.6.4",
              "status": "affected",
              "version": "3.6.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.5.8",
              "status": "affected",
              "version": "3.5.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.4.7",
              "status": "affected",
              "version": "3.4.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.0.22",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.1.1zi",
              "status": "affected",
              "version": "1.1.1",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "openssl-security@openssl.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based\non querying the unwrapped key size, but the AES-WRAP-PAD unwrap primitive\ncan write and cleanse more bytes than that query reports, causing an 8-byte\nout-of-bounds heap write.\n\nImpact summary: An attacker who supplies a crafted CMS message can trigger a\ndeterministic 8-byte out-of-bounds heap write when the victim decrypts it\nwith CMS_decrypt(), corrupting the heap and typically resulting in a Denial\nof Service.\n\nCWE: CWE-787: Out-of-bounds Write\n\nDescription: The key-wrap OID is potentially attacker-controlled on the wire.\nCMS unwrapping allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers.\nAn attacker can take a legitimate message and change a single OID byte to\nselect the padded variant while leaving the message otherwise valid. Since\nthe unwrap key is derived from the recipient\u0027s private operation (ECDH key\nagreement or ML-KEM decapsulation), the RFC 5649 integrity check cannot\npass, and the decryption fails with integrity failure.\n\nThe write is a fixed-size (8-byte), fixed-value (zero) heap overflow\nimmediately past the allocation, requires no special configuration, and is\nreachable from the public CMS_decrypt() function. The consequence is\na heap corruption leading to a Denial of Service. The fix in the CMS code\nsizes the unwrap output buffer for the worst case so a failed unwrap cannot\nwrite past the allocation.\n\nFIPS impact: no\n\nAs the CMS code lives outside the FIPS module boundary, no FIPS\nmodules are affected by this CVE."
    }
  ],
  "id": "CVE-2026-63072",
  "lastModified": "2026-08-25T15:16:36.060",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-63072",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-25T14:29:50.344129Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-25T13:19:26.010",
  "references": [
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/2a3dac874c8057c1f0186849bf1ede1ae7b6b756"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/87784ad619af36b8807c2044b3940006fccc1e42"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/9530a5fd1aacaeccdced4478ea2340a480613335"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/9ec2f6d2ae2bcad907cf7ee38584855bafe4979a"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/a0c8ec557d9cac078f032d76cdf684fe743eb382"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://openssl-library.org/news/secadv/20260825.txt"
    }
  ],
  "sourceIdentifier": "openssl-security@openssl.org",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "openssl-security@openssl.org",
      "type": "Secondary"
    }
  ]
}



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