TI-2026-19253 Aliases CVE-2026-23897 GHSA-mp6q-xf9x-fwf7

Apollo Server is vulnerable to denial of service with `startStandaloneServer`

MEDIUM 40CWE-1333Published 2026-02-04 · Updated 2026-02-04

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-1333.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00689 52nd percentileScored 2026-11-07

Fix Fixed apollo-server (apollographql): 4.13.0, 5.4.0@apollo/server (npm): 4.13.0, 5.4.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
apollographql	apollo-server	2.0.0 – 3.13.0; 4.2.0 to before 4.13.0; 5.0.0 to before 5.4.0	4.13.0, 5.4.0	Patch available	CNA
—	apollo-server (npm)	2.0.0 – 3.13.0	—	No fix listed	GHSA-mp6q-xf9x-fwf7
—	@apollo/server (npm)	4.2.0 to before 4.13.0	4.13.0	Patch available	GHSA-mp6q-xf9x-fwf7
—	@apollo/server (npm)	5.0.0 to before 5.4.0	5.4.0	Patch available	GHSA-mp6q-xf9x-fwf7

apollo-server Vendorapollographql Affected 2.0.0 – 3.13.0; 4.2.0 to before 4.13.0; 5.0.0 to before 5.4.0 Fixed in 4.13.0, 5.4.0 Patch available CNA
apollo-server (npm) Vendor— Affected 2.0.0 – 3.13.0 Fixed in — No fix listed GHSA-mp6q-xf9x-fwf7
@apollo/server (npm) Vendor— Affected 4.2.0 to before 4.13.0 Fixed in 4.13.0 Patch available GHSA-mp6q-xf9x-fwf7
@apollo/server (npm) Vendor— Affected 5.0.0 to before 5.4.0 Fixed in 5.4.0 Patch available GHSA-mp6q-xf9x-fwf7

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:apollographql:apollo_server::::::::	2.0.0 – 3.13.0; 4.2.0 to before 4.13.0; 5.0.0 to before 5.4.0	Vulnerable	apollographql

cpe:2.3:a:apollographql:apollo_server:*:*:*:*:*:*:*:* Versions 2.0.0 – 3.13.0; 4.2.0 to before 4.13.0; 5.0.0 to before 5.4.0 Vulnerable ·apollographql

Remediation

Fix · CNA apollo-server (apollographql) Fixed in 4.13.0, 5.4.0
Fix · GHSA-mp6q-xf9x-fwf7 @apollo/server (npm) Fixed in 4.13.0 Advisory →
Fix · GHSA-mp6q-xf9x-fwf7 @apollo/server (npm) Fixed in 5.4.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-23897
2026-10-03 Alias added: GHSA-mp6q-xf9x-fwf7

References

Patch 2

Advisory 2

Other 1

https://github.com/apollographql/apollo-server

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences