What’s Vulnerable › Vulnerabilities

CVE-2022-23631: Prototype Pollution leading to Remote Code Execution in superjson

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-02-09 · updated 2026-06-17
• Weakness: CWE-94

Description

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.

Affected products

• Blitzjs Blitz: before 0.45.3 — fixed in 0.45.3
• Blitzjs Superjson: before 1.8.1 — fixed in 1.8.1

How to fix

Upgrade to a fixed version: Blitzjs Blitz 0.45.3; Blitzjs Superjson 1.8.1. Check the vendor advisory for mitigations.

References

• https://github.com/advisories/GHSA-5888-ffcr-r425
• https://github.com/blitz-js/superjson/security/advisories/GHSA-5888-ffcr-r425
• https://www.sonarsource.com/blog/blitzjs-prototype-pollution/
• https://github.com/advisories/GHSA-5888-ffcr-r425
• https://github.com/blitz-js/superjson/security/advisories/GHSA-5888-ffcr-r425
• https://www.sonarsource.com/blog/blitzjs-prototype-pollution/

Get alerted when CVE-2022-23631 or the next vulnerability affects your stack