CVE-2026-23897
Apollo Server is an open-source, spec-compliant GraphQL server that's compatible with any GraphQL client, including Apollo Client. In versions from 2.0.0 to 3.13.0, 4.2.0 to before 4.13.0, and 5.0.0 to before 5.4.0, the default configuration of startStandaloneServer from @apollo/server/standalone is vulnerable to denial of service (DoS) attacks through specially crafted request bodies with exotic character set encodings. This issue does not affect users that use @apollo/server as a dependency for integration packages, like @as-integrations/express5 or @as-integrations/next, only direct usage of startStandaloneServer.
Scoring
- Severity
- HIGH
- CVSS base score
- 7.5
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS probability
- 0.64%
- CWE
- CWE-1333
- Published
- 2026-02-04
- Last modified
- 2026-03-12
Affected products
- apollographql apollo-server
- apollographql apollo-server
- apollographql apollo-server
Weakness type
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