The Express team has released body-parser 1.20.6 and 2.3.0, addressing a denial of service vulnerability triggered by invalid limit values.
Warning
We recommend upgrading to the latest version of body-parser to secure your applications. If you have a package-lock.json, you can update the dependency by running:
npm update body-parserThe following vulnerability has been addressed:
CVE-2026-12590 in body-parser middleware (Low)
body-parser versions < 1.20.6 and >= 2.0.0, < 2.3.0 are vulnerable to denial of service when an invalid limit value silently disables size enforcement
When body-parser was configured with an invalid limit option value, such as an unparsable string or NaN, the internal call to bytes.parse() returned null and the request body size check was silently skipped. Applications that relied on limit as their primary safeguard against oversized request bodies would accept arbitrarily large payloads, leading to excessive memory and CPU usage and denial of service. This affected applications that pass a programmatically computed or user-configurable value to the limit option without validating it first. After the fix, invalid limit values throw a clear error at parser construction time instead of silently disabling enforcement.
Affected versions: < 1.20.6 and >= 2.0.0, < 2.3.0
Patched versions: >= 1.20.6 and >= 2.3.0
For more details, see GHSA-v422-hmwv-36x6.
We recommend upgrading to the latest version of body-parser to secure your applications.



