{"id":"CVE-2026-3256","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-3256","generatedAt":"2026-10-28T05:26:17.935Z","title":"HTTP::Session versions before 0.54 for Perl defaults to using insecurely generated session ids.","description":"HTTP::Session versions before 0.54 for Perl defaults to using insecurely generated session ids.\n\nHTTP::Session defaults to using HTTP::Session::ID::SHA1 to generate session ids using a SHA-1 hash seeded with the built-in rand function, the high resolution epoch time, and the PID. The PID will come from a small set of numbers, and the epoch time may be guessed, if it is not leaked from the HTTP Date header. The built-in rand function is unsuitable for cryptographic usage.\n\nThe distribution includes HTTP::session::ID::MD5 which contains a similar flaw, but uses the MD5 hash instead.","published":"2026-03-28T19:16:57.000Z","lastModified":"2026-06-29T07:16:25.000Z","status":"Modified","sourceIdentifier":"9b29abf9-4ab0-4765-b253-1875cd9b441e","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-338","CWE-340"],"affected":["ktat/http\\"],"epss":{"score":0.0054,"percentile":0.45219,"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 (0.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/MD5.pm","tags":["Product"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"https://metacpan.org/release/KTAT/http-session-0.53/source/lib/HTTP/Session/ID/SHA1.pm","tags":["Product"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"https://metacpan.org/release/TOKUHIROM/http-session-0.54/changes","source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"https://security.metacpan.org/docs/guides/random-data-for-security.html","tags":["Third Party Advisory"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"http://www.openwall.com/lists/oss-security/2026/03/28/5","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-3256","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."}