CVE-2026-40991
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedWhen 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.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceWhen using spring-restdocs-webtestclient or spring-restdocs-restassured to document remote APIs over HTTP, the documentation-generating tests parse XML responses from those APIs. A compromised or malicious remote API can inject XXE payloads into its XML responses, which get processed when the documentation tests execute, leading to XXE injection.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 2.0.0, < 2.0.9>= 3.0.0, < 3.0.5.1= 4.0.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- High
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:L
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Spring REST Docs versionCheck your project's dependency management file (pom.xml for Maven or build.gradle for Gradle) for spring-restdocs-webtestclient or spring-restdocs-restassured dependency and note the versionAffected if The version is 2.0.0 through 2.0.8, 3.0.0 through 3.0.5, or exactly 4.0.0
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Verify webtestclient or restassured module usageReview your test source files for imports and configuration of org.springframework.restdocs.webtestclient or org.springframework.restdocs.restassured packagesAffected if Either module is present in your project dependencies or test code
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Confirm XML response parsing in documentation testsExamine your REST Docs test configuration and snippet descriptors to see if documentation is generated for XML-formatted HTTP responsesAffected if Tests generate documentation snippets for XML responses from remote APIs
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Identify remote APIs being documentedReview your test configuration for base URIs or endpoint URLs being used with webtestclient or restassured documentation generationAffected if Tests document responses from APIs that are not under your direct control or are shared/third-party services
You are affected if your environment uses Spring REST Docs version 2.0.0-2.0.8, 3.0.0-3.0.5, or 4.0.0 with the webtestclient or restassured module to document XML responses from external or untrusted remote HTTP APIs
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped2.0.93.0.5.1
Upgrade to a patched version of Spring REST Docs. Until then, avoid documenting untrusted remote APIs and validate/sanitize all API responses before documentation generation.
2.0.9 for 2.x users; 3.0.5.1 for 3.x users; 4.0.1 or later for 4.x users
- 1. Identify your current Spring REST Docs version by checking your build configuration (pom.xml, build.gradle, or equivalent)
- 2. If using version 2.0.x (2.0.0 through 2.0.8): upgrade spring-restdocs-webtestclient and spring-restdocs-restassured dependencies to version 2.0.9
- 3. If using version 3.0.x (3.0.0 through 3.0.5): upgrade spring-restdocs-webtestclient and spring-restdocs-restassured dependencies to version 3.0.5.1
- 4. If using version 4.0.0: upgrade to version 4.0.1 or later (4.x latest stable release)
- 5. Rebuild and run your test suite to verify the upgrade does not break existing functionality
- 6. Ensure your documentation-generating tests still produce the expected API documentation output
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-40991 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-40991 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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