{"id":"CVE-2026-61500","state":"PUBLISHED","title":"Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key","description":"Rejetto HFS 3.0.0 through 3.2.0 derives its session-cookie signing key from the non-cryptographic Math.random() generator and discloses outputs of the same generator to unauthenticated clients during login. A remote attacker can collect a small number of login responses, reconstruct the generator's state, recover the signing key, and forge a valid administrator session cookie, leading to full administrative access and remote code execution via the server_code configuration feature.","publishedAt":"2026-07-13T17:21:55.747Z","updatedAt":"2026-10-01T15:20:09.180Z","severity":{"score":9.3,"label":"Critical","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["rejetto hfs"],"affected":[{"vendor":"rejetto","product":"hfs","packageURL":"pkg:github/rejetto/hfs","defaultStatus":"affected","versions":[{"version":"3.0.0","status":"affected","lessThan":"3.2.1","versionType":"semver"}],"repo":"https://github.com/rejetto/hfs"}],"references":["https://github.com/rejetto/hfs/releases/tag/v3.2.1","https://www.vulncheck.com/advisories/rejetto-hfs-session-forgery-via-predictable-signing-key"],"weaknesses":["CWE-338"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/61xxx/CVE-2026-61500.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-61500","state":"PUBLISHED","datePublished":"2026-07-13T17:21:55.747Z","dateUpdated":"2026-10-01T15:20:09.180Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-07-10T15:43:36.625Z"},"containers":{"cna":{"title":"Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key","descriptions":[{"lang":"en","value":"Rejetto HFS 3.0.0 through 3.2.0 derives its session-cookie signing key from the non-cryptographic Math.random() generator and discloses outputs of the same generator to unauthenticated clients during login. 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