CVEvulnerability

CVE-2022-39218

7.5 HIGH Published 2022-09-20 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2022-09-20
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS 3.1 ([email protected])
7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weaknesses
CWE-335

Description

The JS Compute Runtime for Fastly's Compute@Edge platform provides the environment JavaScript is executed in when using the Compute@Edge JavaScript SDK. In versions prior to 0.5.3, the `Math.random` and `crypto.getRandomValues` methods fail to use sufficiently random values. The initial value to seed the PRNG (pseudorandom number generator) is baked-in to the final WebAssembly module, making the sequence of random values for that specific WebAssembly module predictable. An attacker can use the fixed seed to predict random numbers generated by these functions and bypass cryptographic security controls, for example to disclose sensitive data encrypted by functions that use these generators. The problem has been patched in version 0.5.3. No known workarounds exist.

Affected configurations

• fastly js-compute (< 0.5.3)

Related

Weakness · CWE (1)

  • CWE-335 Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG) weakness

Referenced by CWE · observed example (1)

  • CWE-336 Same Seed in Pseudo-Random Number Generator (PRNG) weakness

References