{"id":"CVE-2018-9127","url":"https://www.cyber-defence.io/tools/cve/CVE-2018-9127","generatedAt":"2026-10-29T01:51:51.978Z","title":"Botan 2.2.0 - 2.4.0 (fixed in 2.5.0) improperly handled wildcard certificates and could accept certain certificates as valid for hostnames when, under RFC 6125 rules, they should not match.","description":"Botan 2.2.0 - 2.4.0 (fixed in 2.5.0) improperly handled wildcard certificates and could accept certain certificates as valid for hostnames when, under RFC 6125 rules, they should not match. This only affects certificates issued to the same domain as the host, so to impersonate a host one must already have a wildcard certificate matching other hosts in the same domain. For example, b*.example.com would match some hostnames that do not begin with a 'b' character.","published":"2018-04-02T17:29:00.000Z","lastModified":"2026-06-17T02:06:07.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-295"],"affected":["botan project/botan"],"epss":{"score":0.0093,"percentile":0.60419,"date":"2026-10-27","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 (0.93%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://botan.randombit.net/security.html","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://botan.randombit.net/security.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2018-9127","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."}