Prototype Pollution leading to Remote Code Execution in superjson
Impact
This is critical vulnerability, as it allows to run arbitrary code on any server using superjson input, including a Blitz.js server, without prior authentication or knowledge. Attackers gain full control over the server so they could steal and manipulate data or attack further systems. The only requirement is that the server implements at least one endpoint which uses superjson during request processing. In the case of Blitz.js, it would be at least one RPC call.
Patches
This has been patched in superjson 1.8.1 and Blitz.js 0.45.3.
If you are unable to upgrade to Blitz.js 0.45.3 in a timely manner, you can instead upgrade only superjson to version 1.8.1 using yarn resolutions are similar. Blitz versions < 0.45.3 are only affected because they used superjson versions < 1.8.1.
Workarounds
None
For more information
If you have any questions or comments about this advisory:
- Open an issue in https://github.com/blitz-js/superjson
- Email us at b@bayer.ws
References
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | blitz | < 0.45.3 | 0.45.3 |
| npm package | superjson | < 1.8.1 | 1.8.1 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H- Weakness (CWE)
CWE-1321, CWE-94- Platform
- npm
- Package
blitz, superjson- Disclosed
- 09.02.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-5888-ffcr-r425 - CC BY 4.0
Vulnerability history: superjson
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
This is the only known vulnerability of this package.
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