Spring REST Docs REST Assured & WebFlux are vulnerable to Improper Restriction of XML External Entity Reference

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:L

EPSS

• CVE-2026-40991: 0.22% estimated exploitation activity in the next 30 days; percentile 12.94 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

When using spring-restdocs-webtestclient or spring-restdocs-restassured to document a remote API accessed over HTTP, an attacker who compromises the API or tricks the user into documenting a malicious API can perform an XXE injection attack when the documentation-generating tests are next executed. Affected versions: Spring REST Docs 4.0.0; 3.0.0 through 3.0.5; 2.0.0.RELEASE through 2.0.8.RELEASE.

Published by the source

10 Jun 2026, 00:31 UTC

Last modified by the source

12 Aug 2026, 15:26 UTC

Source last checked

26 Oct 2026, 16:54 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-6rpq-6vv2-5222

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# Patch Next advisory brief: CVE-2026-40991

Advisory: Spring REST Docs REST Assured & WebFlux are vulnerable to Improper Restriction of XML External Entity Reference
IDs: CVE-2026-40991, GHSA-6rpq-6vv2-5222
Record: https://patchnext.com/advisories/cve-2026-40991 (revision 1, source checked 26 Oct 2026, 16:54 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: org.springframework.restdocs:spring-restdocs-restassured 4.0.1, 3.0.6; org.springframework.restdocs:spring-restdocs-webtestclient 4.0.1, 3.0.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.springframework.restdocs:spring-restdocs-restassured: affected >= 4.0.0, <= 4.0.0; >= 3.0.0, <= 3.0.5; <= 2.0.8.RELEASE; fixed in 3.0.6, 4.0.1
- Maven org.springframework.restdocs:spring-restdocs-webtestclient: affected >= 4.0.0, <= 4.0.0; >= 3.0.0, <= 3.0.5; <= 2.0.8.RELEASE; fixed in 3.0.6, 4.0.1

## Suggested inspection (read-only)
- Maven org.springframework.restdocs:spring-restdocs-restassured: check the installed version with your package manager.
- Maven org.springframework.restdocs:spring-restdocs-webtestclient: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.springframework.restdocs:spring-restdocs-restassured, org.springframework.restdocs:spring-restdocs-webtestclient.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-6rpq-6vv2-5222 (GitHub-reviewed advisory GHSA-6rpq-6vv2-5222 lists affected ranges: Maven org.springframework.restdocs:spring-restdocs-webtestclient >=4.0.0 =3.0.0 =0 =4.0.0 =3.0.0 =0 <=2.0.8.RELEASE)

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