Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) Affecting hfs package, versions >=3.0.0 <3.2.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published14 Jul 2026
- disclosed13 Jul 2026
- creditZach Hanley
Introduced: 13 Jul 2026
NewCVE-2026-61500 (opens in a new tab)How to fix?
Upgrade hfs to version 3.2.1 or higher.
Overview
hfs is a HTTP File Server
Affected versions of this package are vulnerable to Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) via predictable randomness in the authentication/session handling code in src/index.ts and src/api.auth.ts. An attacker can forge an administrator session cookie by collecting a few login responses, reconstructing the Math.random() state used to derive the session-signing key and login handshake identifier, and then generating a valid cookie. This breaks authentication and gives the attacker full administrative access to the server. In deployments that expose the server_code configuration feature, that access leads to remote code execution.