FKIE_CVE-2026-54872

Vulnerability from fkie_nvd - Published: 2026-09-29 16:17 - Updated: 2026-09-29 21:27
Severity
3.7 (Low) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Summary
Issue summary: The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature operations with curves that do not have a dedicated implementation leaks information about the secret nonce through timing. Impact summary: An attacker able to measure signing times may learn information about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy Description: The generic elliptic-curve scalar multiplication used for curves that do not have a dedicated constant-time implementation pads the secret scalar with non-constant-time BIGNUM operations, so the time taken depends on the value of the secret scalar derived from the ECDSA and SM2 nonce. The leak is very small; observing it requires a large number of measurements. The effect is largest for curves whose group order lies on a machine-word boundary, such as brainpoolP384r1. Applications using ECDSA signing over the Brainpool and other generic prime curves, and SM2 signing on platforms that use the generic implementation, are vulnerable to this issue. The NIST curves P-256, P-384 and P-521 use dedicated constant-time implementations and are not affected. FIPS Impact: no The FIPS modules are not affected: the approved NIST curves used in the FIPS provider have dedicated constant-time implementations and do not use the affected code path.
References
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/1a5bee8dc57430a2be69cd1ffe7fec6a62f4f179
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/3f7e1363dccec6f7732bb9e9fa471bb6e4aa68cb
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/7d83bc7764999dfd91b83b4f0815b45390422afd
openssl-security@openssl.orghttps://github.com/openssl/openssl/commit/8166827a78aad164a07aa86dea2b425403ced471
openssl-security@openssl.orghttps://openssl-library.org/news/secadv/20260929.txt
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "4.0.3",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.6.5",
              "status": "affected",
              "version": "3.6.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.5.9",
              "status": "affected",
              "version": "3.5.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.4.8",
              "status": "affected",
              "version": "3.4.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.0.23",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.1.1zj",
              "status": "affected",
              "version": "1.1.1",
              "versionType": "custom"
            },
            {
              "lessThan": "1.0.2zs",
              "status": "affected",
              "version": "1.0.2",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "openssl-security@openssl.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Issue summary: The generic elliptic-curve scalar multiplication used for\nECDSA and SM2 signature operations with curves that do not have a dedicated\nimplementation leaks information about the secret nonce through timing.\n\nImpact summary: An attacker able to measure signing times may learn\ninformation about the per-signature secret nonce, which over many signatures\ncan, via a lattice / Hidden Number Problem attack, lead to recovery of the\nprivate key.\n\nCWE: CWE-208: Observable Timing Discrepancy\n\nDescription: The generic elliptic-curve scalar multiplication used for\ncurves that do not have a dedicated constant-time implementation pads the\nsecret scalar with non-constant-time BIGNUM operations, so the time taken\ndepends on the value of the secret scalar derived from the ECDSA and SM2 nonce.\n\nThe leak is very small; observing it requires a large number of\nmeasurements. The effect is largest for curves whose group order lies\non a machine-word boundary, such as brainpoolP384r1.\n\nApplications using ECDSA signing over the Brainpool and other generic prime\ncurves, and SM2 signing on platforms that use the generic implementation,\nare vulnerable to this issue.\n\nThe NIST curves P-256, P-384 and P-521 use dedicated constant-time\nimplementations and are not affected.\n\nFIPS Impact: no\nThe FIPS modules are not affected: the approved NIST curves used in the FIPS\nprovider have dedicated constant-time implementations and do not use the\naffected code path."
    }
  ],
  "id": "CVE-2026-54872",
  "lastModified": "2026-09-29T21:27:41.130",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 3.7,
          "baseSeverity": "LOW",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 1.4,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-54872",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-29T17:27:46.959054Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-29T16:17:08.623",
  "references": [
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/1a5bee8dc57430a2be69cd1ffe7fec6a62f4f179"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/3f7e1363dccec6f7732bb9e9fa471bb6e4aa68cb"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/7d83bc7764999dfd91b83b4f0815b45390422afd"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://github.com/openssl/openssl/commit/8166827a78aad164a07aa86dea2b425403ced471"
    },
    {
      "source": "openssl-security@openssl.org",
      "url": "https://openssl-library.org/news/secadv/20260929.txt"
    }
  ],
  "sourceIdentifier": "openssl-security@openssl.org",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-208"
        }
      ],
      "source": "openssl-security@openssl.org",
      "type": "Secondary"
    }
  ]
}



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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.