{"basis":"claimed","id":"CVE-2026-61500","name":"Rejetto HFS < 3.2.1 Session Forgery via Predictable Signing Key","vendorProject":"rejetto","product":"hfs","publishedAt":"2026-07-13","cvss":{"score":9.3,"severity":"CRITICAL","version":"4.0"},"exploited":null,"epss":{"score":0.01908,"percentile":0.7977,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"none","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-10-21","daysToRule":100},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"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.","cwes":["CWE-338"],"vendors":[{"vendor":"cloudflare","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-10-21","firstIsNew":true,"daysToRule":100,"daysAtMost":null,"freePlan":false,"claims":[{"id":"81877326c99eba213ff7d01a611f1fc68d4fb3496c4462a5e8c492b80f2398e4","cve_id":"CVE-2026-61500","vendor":"f5","product":"Attack signatures","rule_id":"200204110","rule_name":"Rejetto HFS Remote Code Execution (2)","change":"new","default_action":null,"published_on":"2026-10-21","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200204110 \"Rejetto HFS Remote Code Execution (2)\" (Server Side Code Injection, risk High), systems: Microsoft Windows, Other Web Server. References: CVE-2026-61500.","first_seen_at":"2026-11-02T21:00:23.824Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-02T21:17:16.628Z","cvssVector":"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","ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total"},"measured":[],"social":{"total":0,"first_seen":null,"daily":[{"day":"2026-10-20","posts":0},{"day":"2026-10-21","posts":0},{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0}],"top_posts":[],"exploit_repositories":[]}}