CVE-2026-61500

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/rejetto/hfs/releases/tag/v3.2.1
https://www.vulncheck.com/advisories/rejetto-hfs-session-forgery-via-predictable-signing-key

Configurations

No configuration.

History

13 Jul 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-13 18:16

Updated : 2026-07-15 15:16

NVD link : CVE-2026-61500

Mitre link : CVE-2026-61500

CVE.ORG link : CVE-2026-61500

JSON object : View

Products Affected

No product.

CWE

CWE-338

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

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