{"id":"CVE-2020-10185","url":"https://www.cyber-defence.io/tools/cve/CVE-2020-10185","generatedAt":"2026-10-27T21:17:04.706Z","title":"The sync endpoint in YubiKey Validation Server before 2.40 allows remote attackers to replay an OTP.","description":"The sync endpoint in YubiKey Validation Server before 2.40 allows remote attackers to replay an OTP. NOTE: this issue is potentially relevant to persons outside Yubico who operate a self-hosted OTP validation service with a non-default configuration such as an open sync pool; the issue does NOT affect YubiCloud.","published":"2020-03-05T23:15:13.000Z","lastModified":"2026-06-17T02:47:28.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H"},"cwe":["CWE-294"],"affected":["yubico/yubikey one time password validation server"],"epss":{"score":0.01682,"percentile":0.76803,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.68%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/Yubico/yubikey-val/releases/tag/yubikey-val-2.40","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.debian.org/debian-lts-announce/2020/03/msg00014.html","source":"cve@mitre.org"},{"url":"https://www.yubico.com/support/security-advisories/ysa-2020-01/","tags":["Exploit","Vendor Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/Yubico/yubikey-val/releases/tag/yubikey-val-2.40","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2020/03/msg00014.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.yubico.com/support/security-advisories/ysa-2020-01/","tags":["Exploit","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2020-10185","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}