{"id":"CVE-2026-25793","published":"2026-02-06T22:55:36Z","modified":"2026-02-09T15:25:50Z","title":"Nebula Has Possible Blocklist Bypass via ECDSA Signature Malleability","vendor":"slackhq","product":"nebula","tier":"tail","description":{"text":"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.","provenance":"source","from":"CVE.org"},"cvss":{"score":7.6,"severity":"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","provenance":"source","from":"CVE.org CNA"},"epss":{"score":0.00145,"percentile":0.03721,"provenance":"source"},"cwes":[{"id":"CWE-347","name":"Improper Verification of Cryptographic Signature"}],"references":[{"url":"https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21","tags":["x_refsource_MISC"]}],"priority":{"score":6.1,"factors":[{"name":"EPSS percentile","points":0.74},{"name":"CVSS severity","points":5.32}]},"vendorSlug":"slackhq","affectedVersions":[{"vendor":"slackhq","product":"nebula","versions":[">= 1.7.0, < 1.10.3"]}],"affected":[{"ecosystem":"Go","package":"github.com/slackhq/nebula","vulnerableRanges":[">=1.7.0, <1.10.3"],"patched":["1.10.3"],"from":["GHSA-69x3-g4r3-p962","GO-2026-4458"],"provenance":"source"}],"euvd":{"id":"EUVD-2026-6933","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-openzeppelin-contracts-cve-2022-35961","children":[{"from":"CVE-2026-25793","to":"CVE-2026-33895","relation":"related","confidence":"high","kind":"lineage","evidence":[{"kind":"osv-related","provenance":"source","id":"GHSA-q67f-28xg-22rw","via":"reference","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25793"}]}],"packageHistory":[{"cve":"CVE-2025-62820","published":"2025-10-23","fixed":"1.9.7","kev":false,"link":{"from":"CVE-2025-62820","to":"CVE-2026-25793","relation":"successor","confidence":"low","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"Go:github.com/slackhq/nebula","fromFixed":"1.9.7","toFixed":"1.10.3","daysApart":106}]}},{"cve":"CVE-2026-25793","published":"2026-02-06","fixed":"1.10.3","kev":false}],"package":"Go:github.com/slackhq/nebula"}}