CVE-2026-40991 | XML External Entity (XXE) injection when documenting untrusted XML content

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: 2026-06-09 Last update: 2026-06-27 Assigner: [email protected] Source: [email protected]
NVD Status：Undergoing Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-40991 is rated Low Risk (28.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.22%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-40991

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.22% +0.18%
2 2026-06-10 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40991

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.6 4.2 [email protected]

Weakness enumeration for CVE-2026-40991

GitHub Security Advisory for CVE-2026-40991

GHSA-6rpq-6vv2-5222 · Severity: medium — When using spring-restdocs-webtestclient or spring-restdocs-restassured to document a remote API...

Affected software / configurations for CVE-2026-40991

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-40991

cvelogic Threat Intelligence