# CVE-2026-23897: Apollo Server is vulnerable to denial of service with `startStandaloneServer`

> CVE-2026-23897: Apollo Server is vulnerable to denial of service with `startStandaloneServer`. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-23897
Last updated: 2026-06-17T10:22:16Z

- Published: 2026-02-04 19:18 UTC · Updated: 2026-06-17 10:22 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.70%, 53th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-1333

## Description

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.

## Affected vendors and products

- apollographql: apollo-server

## Tracked companies

- [Apollo GraphQL](https://rewindex.com/company/apollo-graphql.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-23897)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-23897)
- [https://github.com/apollographql/apollo-server/commit/d25a5bdc377826ad424fcf7f8d1d062055911643](https://github.com/apollographql/apollo-server/commit/d25a5bdc377826ad424fcf7f8d1d062055911643)
- [https://github.com/apollographql/apollo-server/commit/e9d49d163a86b8a33be56ed27c494b9acd5400a4](https://github.com/apollographql/apollo-server/commit/e9d49d163a86b8a33be56ed27c494b9acd5400a4)
- [https://github.com/apollographql/apollo-server/security/advisories/GHSA-mp6q-xf9x-fwf7](https://github.com/apollographql/apollo-server/security/advisories/GHSA-mp6q-xf9x-fwf7)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-23897 · Markdown: https://rewindex.com/cve/CVE-2026-23897.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-23897 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:15:30.550Z