High severity · published Jan 9, 2023
CVE-2023-22477
Mercurius is vulnerable to denial of service (DoS) when using subscriptions
7.5
CVSS
1.1%
EPSS
No
On KEV
Description
Mercurius is a GraphQL adapter for Fastify. Any users of Mercurius until version 10.5.0 are subjected to a denial of service attack by sending a malformed packet over WebSocket to `/graphql`. This issue was patched in #940. As a workaround, users can disable subscriptions.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ME
mercurius · mercurius-js
< 10.5.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-22477
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-22477
Exploit
https://github.com/mercurius-js/mercurius/issues/939
Patch
https://github.com/mercurius-js/mercurius/pull/940
Patch
https://github.com/mercurius-js/mercurius/security/advisories/GHSA-cm8h-q92v-xcfc
More from mercurius
8.2
CVE-2026-30241
Mercurius: queryDepth limit bypassed for WebSocket subscriptions
5.4
CVE-2025-64166
Mercurius: Incorrect Content-Type parsing can lead to CSRF attack