{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "4.1.1",
              "status": "affected",
              "version": "4.1.0",
              "versionType": "semver"
            },
            {
              "lessThan": "4.0.4",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.5.10",
              "status": "affected",
              "version": "3.5.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.0.24",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.1.1zk",
              "status": "affected",
              "version": "1.1.1",
              "versionType": "custom"
            },
            {
              "lessThan": "1.0.2zt",
              "status": "affected",
              "version": "1.0.2",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Yinxi Liu"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Jakub Zelenka"
        }
      ],
      "datePublic": "2026-11-10T11:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Issue summary: Encrypting a CMS message to an EC certificate whose group order\u003cbr\u003eis 1 may cause CMS_encrypt() or CMS_encrypt_ex() to loop indefinitely.\u003cbr\u003e\u003cbr\u003eImpact summary: An attacker able to supply the recipient certificate to an\u003cbr\u003eapplication performing CMS encryption can cause that application to loop\u003cbr\u003eindefinitely, consuming CPU and resulting in Denial of Service.\u003cbr\u003e\u003cbr\u003eCWE: CWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)\u003cbr\u003e\u003cbr\u003eDescription: CMS_encrypt() and CMS_encrypt_ex() encrypt a message to one or\u003cbr\u003emore recipient certificates and, for an EC recipient, generate an ephemeral\u003cbr\u003ekey in the recipient\u0027s group. If the certificate declares a group order of 1,\u003cbr\u003erandom scalar generation can only produce zero. The key generation routine\u003cbr\u003ethen retries without limit while waiting for a nonzero private scalar, so the\u003cbr\u003ecall never returns.\u003cbr\u003e\u003cbr\u003eThe OpenSSL TLS and QUIC implementations do not use this path. An application\u003cbr\u003eis exposed only if it calls CMS_encrypt() or CMS_encrypt_ex() with a recipient\u003cbr\u003ecertificate whose EC parameters are attacker-controlled. Certificates with\u003cbr\u003enormal EC group orders do not trigger the loop.\u003cbr\u003e\u003cbr\u003eOpenSSL 4.0 and later reject unknown explicit EC groups in default builds.\u003cbr\u003eThese versions are affected only when configured with the\u003cbr\u003eenable-ec_explicit_curves option.\u003cbr\u003e\u003cbr\u003eThe result is a hang that consumes a CPU core until the process is\u003cbr\u003einterrupted, a Denial of Service. The severity is Low because the attacker\u003cbr\u003emust supply the recipient certificate and the application must choose to\u003cbr\u003eencrypt to it; ordinary CMS encryption to trusted recipients is unaffected.\u003cbr\u003e\u003cbr\u003eThe fix makes EC key generation fail when the group has no valid nonzero\u003cbr\u003eprivate scalar, instead of retrying indefinitely.\u003cbr\u003e\u003cbr\u003eFIPS impact: no\u003cbr\u003eThe FIPS modules in 4.1, 4.0, 3.5 and 3.0 are not affected. The FIPS provider\u003cbr\u003edoes not support arbitrary explicit EC domain parameters, so an order-1 group\u003cbr\u003eis rejected during key import before the vulnerable key generation path is\u003cbr\u003ereached."
            }
          ],
          "value": "Issue summary: Encrypting a CMS message to an EC certificate whose group order\nis 1 may cause CMS_encrypt() or CMS_encrypt_ex() to loop indefinitely.\n\nImpact summary: An attacker able to supply the recipient certificate to an\napplication performing CMS encryption can cause that application to loop\nindefinitely, consuming CPU and resulting in Denial of Service.\n\nCWE: CWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)\n\nDescription: CMS_encrypt() and CMS_encrypt_ex() encrypt a message to one or\nmore recipient certificates and, for an EC recipient, generate an ephemeral\nkey in the recipient\u0027s group. If the certificate declares a group order of 1,\nrandom scalar generation can only produce zero. The key generation routine\nthen retries without limit while waiting for a nonzero private scalar, so the\ncall never returns.\n\nThe OpenSSL TLS and QUIC implementations do not use this path. An application\nis exposed only if it calls CMS_encrypt() or CMS_encrypt_ex() with a recipient\ncertificate whose EC parameters are attacker-controlled. Certificates with\nnormal EC group orders do not trigger the loop.\n\nOpenSSL 4.0 and later reject unknown explicit EC groups in default builds.\nThese versions are affected only when configured with the\nenable-ec_explicit_curves option.\n\nThe result is a hang that consumes a CPU core until the process is\ninterrupted, a Denial of Service. The severity is Low because the attacker\nmust supply the recipient certificate and the application must choose to\nencrypt to it; ordinary CMS encryption to trusted recipients is unaffected.\n\nThe fix makes EC key generation fail when the group has no valid nonzero\nprivate scalar, instead of retrying indefinitely.\n\nFIPS impact: no\nThe FIPS modules in 4.1, 4.0, 3.5 and 3.0 are not affected. The FIPS provider\ndoes not support arbitrary explicit EC domain parameters, so an order-1 group\nis rejected during key import before the vulnerable key generation path is\nreached."
        }
      ],
      "metrics": [
        {
          "format": "other",
          "other": {
            "content": {
              "text": "Low"
            },
            "type": "https://openssl-library.org/policies/general/security-policy/"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-835",
              "description": "CWE-835 Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-10T18:14:18.207Z",
        "orgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5",
        "shortName": "openssl"
      },
      "references": [
        {
          "name": "OpenSSL Advisory",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://openssl-library.org/news/secadv/20261110.txt"
        },
        {
          "name": "4.1.1 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/36e15b618decdff1b116eead6747718e6e729ad2"
        },
        {
          "name": "4.0.4 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/a8531368ddb1f86d2a2782a8b693926bb67b59e7"
        },
        {
          "name": "3.5.10 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/a0051cfe699bf5a047bc1c4faef65f80f7987366"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Infinite Loop in CMS_encrypt() With an EC Group Order of 1",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5",
    "assignerShortName": "openssl",
    "cveId": "CVE-2026-107496",
    "datePublished": "2026-11-10T18:14:18.207Z",
    "dateReserved": "2026-10-08T08:31:36.278Z",
    "dateUpdated": "2026-11-10T18:14:18.207Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}