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TI-2022-18597 Aliases CVE-2022-39218GHSA-cmr8-5w4c-44v8

Random number seed fixed during compilation

Priority MEDIUM 41CWE-335Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00922 60th percentileScored 2026-11-07
Fix Fixed js-compute-runtime (fastly): 0.5.3@fastly/js-compute (npm): 0.5.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Fastlyjs-compute-runtimebefore 0.5.30.5.3Patch availableCNA
—@fastly/js-compute (npm)0.4.0 to before 0.5.30.5.3Patch availableGHSA-cmr8-5w4c-44v8
  • js-compute-runtime VendorFastly Affected before 0.5.3 Fixed in 0.5.3 Patch available CNA
  • @fastly/js-compute (npm) Vendor— Affected 0.4.0 to before 0.5.3 Fixed in 0.5.3 Patch available GHSA-cmr8-5w4c-44v8

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fastly:js-compute:*:*:*:*:*:node.js:*:*before 0.5.3VulnerableFastly
  • cpe:2.3:a:fastly:js-compute:*:*:*:*:*:node.js:*:* Versions before 0.5.3 Vulnerable ·Fastly

Remediation

  • Fix · CNA js-compute-runtime (fastly) Fixed in 0.5.3
  • Fix · GHSA-cmr8-5w4c-44v8 @fastly/js-compute (npm) Fixed in 0.5.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-39218
  2. 2026-10-03 Alias added: GHSA-cmr8-5w4c-44v8

References

Advisory 2

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences