{"id":"CVE-2026-2439","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-2439","generatedAt":"2026-10-28T03:23:20.079Z","title":"Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids.","description":"Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids. The generate_session_id function in Concierge::Sessions::Base defaults to using the uuidgen command to generate a UUID, with a fallback to using Perl's built-in rand function. Neither of these methods are secure, and attackers are able to guess session_ids that can grant them access to systems. Specifically,\n\n  *  There is no warning when uuidgen fails. The software can be quietly using the fallback rand() function with no warnings if the command fails for any reason.\n  *  The uuidgen command will generate a time-based UUID if the system does not have a high-quality random number source, because the call does not explicitly specify the --random option. Note that the system time is shared in HTTP responses.\n  *  UUIDs are identifiers whose mere possession grants access, as per RFC 9562.\n  *  The output of the built-in rand() function is predictable and unsuitable for security applications.","published":"2026-02-16T22:22:41.000Z","lastModified":"2026-06-17T10:30:57.000Z","status":"Analyzed","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":["bva/concierge\\"],"epss":{"score":0.00468,"percentile":0.40273,"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 (0.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/bwva/Concierge-Sessions/commit/20bb28e92e8fba307c4ff8264701c215be65e73b","tags":["Patch"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"https://metacpan.org/release/BVA/Concierge-Sessions-v0.8.4/diff/BVA/Concierge-Sessions-v0.8.5#lib/Concierge/Sessions/Base.pm","tags":["Product","Release Notes"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"},{"url":"https://perldoc.perl.org/5.42.0/functions/rand","tags":["Third Party Advisory"],"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":"https://www.rfc-editor.org/rfc/rfc9562.html#name-security-considerations","tags":["Third Party Advisory"],"source":"9b29abf9-4ab0-4765-b253-1875cd9b441e"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-2439","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."}