CVE-2021-43801

Uncaught Exception in mercurius

Description

Mercurius is a GraphQL adapter for Fastify. Any users from Mercurius@8.10.0 to 8.11.1 are subjected to a denial of service attack by sending a malformed JSON to `/graphql` unless they are using a custom error handler. The vulnerability has been fixed in https://github.com/mercurius-js/mercurius/pull/678 and shipped as v8.11.2. As a workaround users may use a custom error handler.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.35%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: mercurius-js mercurius
Published at:
Updated at:

References

Link Tags
https://github.com/mercurius-js/mercurius/security/advisories/GHSA-273r-rm8g-7f3x third party advisory patch
https://github.com/mercurius-js/mercurius/issues/677 patch third party advisory issue tracking
https://github.com/mercurius-js/mercurius/pull/678/commits/732b2f895312da8deadd7b173dcd2d141d54b223 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-43801?
CVE-2021-43801 has been scored as a high severity vulnerability.
How to fix CVE-2021-43801?
To fix CVE-2021-43801, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43801 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43801 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43801?
CVE-2021-43801 affects mercurius-js mercurius.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.