Vulnerability in Fastly Js-Compute
CVE-2022-39218
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.009 (59.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 59.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.001
Affected products
- Fastly Js-Compute
- Fastly Js-Compute-Runtime — versions < 0.5.3
Weakness classification (CWE)
References
- github.com/fastly/js-compute-runtime/security/advisories/GHSA-cmr8-5w4c-44v8 (Third Party Advisory)
Frequently asked questions
- What is CVE-2022-39218?
- CVE-2022-39218 is a high-severity vulnerability in Fastly Js-Compute, classified under Incorrect Usage of Seeds in Pseudo-Random Number Generator (PRNG). CVSS score: 7.5/10. Published 2022-09-20.
- How severe is CVE-2022-39218?
- High severity. CVSS v3 base score is 7.5 out of 10.