What is CVE-2021-43801?

CVE-2021-43801 is a high-severity vulnerability in Mercurius-Js Mercurius, classified under Improper Check for Unusual or Exceptional Conditions. CVSS score: 7.5/10. Published 2021-12-13.

How severe is CVE-2021-43801?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Mercurius-Js Mercurius

CVE-2021-43801

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.

EPSS: 0.015 (72.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Mercurius-js Mercurius — versions >= 8.10.0, < 8.11.2
Mercurius_project Mercurius

Weakness classification (CWE)

CWE-754 — Improper Check for Unusual or Exceptional Conditions

References

security-advisories@github.com (x_refsource_CONFIRM, Patch, Third Party Advisory)
security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)

Frequently asked questions

What is CVE-2021-43801?: CVE-2021-43801 is a high-severity vulnerability in Mercurius-Js Mercurius, classified under Improper Check for Unusual or Exceptional Conditions. CVSS score: 7.5/10. Published 2021-12-13.
How severe is CVE-2021-43801?: High severity. CVSS v3 base score is 7.5 out of 10.