{"affected":[{"defaultStatus":"unaffected","product":"OpenSSL","source":"CNA: 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"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"V3.1.7","versionType":"custom"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"V3.1.7","versionType":"custom"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"V3.1.7","versionType":"custom"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"V3.1.7","versionType":"custom"}]},{"defaultStatus":"unknown","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"V3.1.7","versionType":"custom"}]}],"cveId":"CVE-2026-77696","cwes":["CWE-208"],"description":"Issue summary: SM2 signature generation uses non-constant-time arithmetic\non secret values, forming a timing side-channel.\n\nImpact summary: An attacker able to measure SM2 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: SM2 signature generation computes the signature value using\nvariable-time BIGNUM operations on the secret nonce and the private key, so\nthe time taken to produce an SM2 signature depends on these secret values,\nforming a timing side-channel.\n\nApplications performing SM2 signature generation are affected on all\nplatforms.\n\nFIPS Impact: no\nSM2 is not a FIPS algorithm.","epss":{"date":"2026-11-09","percentile":0.3411,"score":0.00396},"exploits":[],"kev":null,"metrics":[{"score":3.7,"severity":"low","source":"ADP: CISA-ADP","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}],"modifiedAt":1794314990567,"publishedAt":1790695942520,"references":[{"source":"CNA: openssl","tags":["vendor-advisory"],"url":"https://openssl-library.org/news/secadv/20260929.txt"},{"source":"CNA: openssl","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/20b20628d39b2dcc4677194bd68c7c060fa598cb"},{"source":"CNA: openssl","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/1c4aed808a7aea32d2d013049c2e0d9fef164fc9"},{"source":"CNA: openssl","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/6b90445a56b99a328ac1feba058abf976504f440"},{"source":"CNA: openssl","tags":["patch"],"url":"https://github.com/openssl/openssl/commit/419f5cb519721dceed393dbc524d79e487c72e64"},{"source":"ADP: siemens-SADP","tags":[],"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}],"remediation":[{"kind":"fix","source":"CNA: openssl","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/openssl/openssl/commit/20b20628d39b2dcc4677194bd68c7c060fa598cb"},{"kind":"fix","source":"CNA: openssl","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/openssl/openssl/commit/1c4aed808a7aea32d2d013049c2e0d9fef164fc9"},{"kind":"fix","source":"CNA: openssl","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/openssl/openssl/commit/6b90445a56b99a328ac1feba058abf976504f440"},{"kind":"fix","source":"CNA: openssl","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/openssl/openssl/commit/419f5cb519721dceed393dbc524d79e487c72e64"}],"revision":"dc0ea812d63ce8898063221f1109e32bf54b8c8fffd67e5d12c58c2de6f83c31","sources":[{"modifiedAt":1794314990567,"name":"CNA: openssl","retrievedAt":1794316760861,"url":"https://www.cve.org/CVERecord?id=CVE-2026-77696"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794316770316,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-77696"}],"ssvc":{"assessedAt":1790700690070,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Timing Side-Channel in SM2 Signature Generation","updatedAt":1794316770316}