CVE-2026-61500
Critical · CVSS 9.8Rejetto HFS (HTTP File Server) — Predictable PRNG session-cookie signing key forgery leading to RCE (CWE-338)
- CVSS
- 9.8
- nvd
- EPSS
- 0.75%
- 51th pct
- KEV
- No
- Class
- oss containerizable
- CWE-338
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.
Search profile — drives PoC discovery
Symbols Math.randomsession-cookiesigning keyserver_codelogincookie forgePRNG state reconstructionHFS 3
Keywords CVE-2026-61500Rejetto HFS session forgeryHFS Math.random signing keyHFS cookie forgery RCErejetto hfs predictable sessionHFS 3.0 3.1 3.2 session tokenrejetto hfs server_code RCEHFS PRNG state reconstructhfs session cookie exploit
Versions: 3.0.0 through 3.2.0
References
Status: enriched · ingested 2026-07-15T00:00:20.000Z · profiled 2026-07-15T06:30:20.000Z