CVE-2022-39218: fastly js-compute
Vulnerability summary
CVE-2022-39218 is a high (CVSS 7.5) vulnerability in fastly js-compute. EPSS estimates a 0.92% chance of exploitation in the next 30 days, higher than 59.7% of scored vulnerabilities.
Timeline
- 20-09-2022PublishedVulnerability first disclosed.
- 23-04-2025Last modifiedVulnerability information updated.
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.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · NpmEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.92%
Chance of exploitation in the next 30 days
Percentile
60%
Versus all other CVEs
30-day change
0.00 pp
From 0.92% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Fastly2 products
- js-compute< 0.5.3
- js-compute-runtime< 0.5.3
@fastly1 product
- js-compute≥ 0.4.0, < 0.5.3
2 vendors · 3 products
References
4 links- github.com/fastly/js-compute-runtime/security/advisories/GHSA-cmr8-5w4c-44v8X Refsource CONFIRMWEBThird Party Advisory
