{"id":"CVE-2023-22465","url":"https://www.cyber-defence.io/tools/cve/CVE-2023-22465","generatedAt":"2026-10-27T18:48:58.737Z","title":"As a workaround, use the weakly typed header interface.","description":"Http4s is a Scala interface for HTTP services. Starting with version 0.1.0 and prior to versions 0.21.34, 0.22.15, 0.23.17, and 1.0.0-M38, the `User-Agent` and `Server` header parsers are susceptible to a fatal error on certain inputs.  In http4s, modeled headers are lazily parsed, so this only applies to services that explicitly request these typed headers. Fixes are released in 0.21.34, 0.22.15, 0.23.17, and 1.0.0-M38. As a workaround, use the weakly typed header interface.","published":"2023-01-04T16:15:09.000Z","lastModified":"2026-06-17T05:35:31.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-20"],"affected":["typelevel/http4s"],"epss":{"score":0.00854,"percentile":0.58026,"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":"low","text":"Lower severity and a low EPSS score (0.85%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/http4s/http4s/security/advisories/GHSA-54w6-vxfh-fw7f","tags":["Exploit","Mitigation","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/http4s/http4s/security/advisories/GHSA-54w6-vxfh-fw7f","tags":["Exploit","Mitigation","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-22465","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."}