What is CVE-2022-23631?

CVE-2022-23631 is a critical-severity vulnerability in Blitz-Js Superjson, classified under Code Injection. CVSS score: 9.0/10. Published 2022-02-09.

How severe is CVE-2022-23631?

Critical severity. CVSS v3 base score is 9.0 out of 10.

RCE in Blitz-Js Superjson

CVE-2022-23631

superjson is a program to allow JavaScript expressions to be serialized to a superset of JSON. In versions prior to 1.8.1 superjson allows input to run arbitrary code on any server using superjson input without prior authentication or knowledge. The only requirement is that the server implements at least one endpoint which uses superjson during request processing. This has been patched in superjson 1.8.1. Users are advised to update. There are no known workarounds for this issue.

Vulnerability class: RCE (Remote Code Execution)

Published 2022-02-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.023 (82.9th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 83rd percentile — 82.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.023 · newest: 0.023 · change: 0.000

Affected products

Weakness classification (CWE)

References

github.com/blitz-js/superjson/security/advisories/GHSA-5888-ffcr-r425 (Exploit, Third Party Advisory)
github.com/advisories/GHSA-5888-ffcr-r425 (Exploit, Third Party Advisory)
www.sonarsource.com/blog/blitzjs-prototype-pollution/ (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2022-23631?: CVE-2022-23631 is a critical-severity vulnerability in Blitz-Js Superjson, classified under Code Injection. CVSS score: 9.0/10. Published 2022-02-09.
How severe is CVE-2022-23631?: Critical severity. CVSS v3 base score is 9.0 out of 10.