{"id":"CVE-2026-25793","state":"PUBLISHED","title":"Nebula Has Possible Blocklist Bypass via ECDSA Signature Malleability","description":"Nebula is a scalable overlay networking tool. In versions from 1.7.0 to 1.10.2, when using P256 certificates (which is not the default configuration), it is possible to evade a blocklist entry created against the fingerprint of a certificate by using ECDSA Signature Malleability to use a copy of the certificate with a different fingerprint. This issue has been patched in version 1.10.3.","publishedAt":"2026-02-06T22:55:36.011Z","updatedAt":"2026-02-09T15:25:50.582Z","severity":{"score":7.6,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["slackhq nebula"],"affected":[{"vendor":"slackhq","product":"nebula","versions":[{"version":">= 1.7.0, < 1.10.3","status":"affected"}]}],"references":["https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962","https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21"],"weaknesses":["CWE-347"],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/25xxx/CVE-2026-25793.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-25793","state":"PUBLISHED","datePublished":"2026-02-06T22:55:36.011Z","dateUpdated":"2026-02-09T15:25:50.582Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-02-05T19:58:01.640Z"},"containers":{"cna":{"title":"Nebula Has Possible Blocklist Bypass via ECDSA Signature Malleability","descriptions":[{"lang":"en","value":"Nebula is a scalable overlay networking tool. In versions from 1.7.0 to 1.10.2, when using P256 certificates (which is not the default configuration), it is possible to evade a blocklist entry created against the fingerprint of a certificate by using ECDSA Signature Malleability to use a copy of the certificate with a different fingerprint. This issue has been patched in version 1.10.3."}],"affected":[{"vendor":"slackhq","product":"nebula","versions":[{"version":">= 1.7.0, < 1.10.3","status":"affected"}]}],"references":[{"url":"https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962","name":"https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21","name":"https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.6,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-347","lang":"en","description":"CWE-347: Improper Verification of Cryptographic Signature","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-02-06T22:55:36.011Z"},"source":{"advisory":"GHSA-69x3-g4r3-p962","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-02-09T15:19:12.820151Z","id":"CVE-2026-25793","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-02-09T15:25:50.582Z"}}]}}}