CVE-2026-42521
Jenkins Matrix Authorization Strategy Plugin Deserialization RCE
Description
Jenkins Matrix Authorization Strategy Plugin 2.0-beta-1 through 3.2.9 (both inclusive) invokes parameterless constructors of classes specified in configuration when deserializing inheritance strategies, without restricting the classes that can be instantiated, allowing attackers with Item/Configure permission to instantiate arbitrary types, which may lead to information disclosure or other impacts depending on the classes available on the classpath.
INFO
Published Date :
April 29, 2026, 2:16 p.m.
Last Modified :
May 6, 2026, 4:21 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update Jenkins Matrix Authorization Strategy Plugin.
- Review and restrict configurable class instantiations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42521.
| URL | Resource |
|---|---|
| https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3676 | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42521 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42521
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42521 vulnerability anywhere in the article.
-
CybersecurityNews
Jenkins Patches High-Severity Plugin Flaws Including Path Traversal and Stored XSS
Jenkins project published a security advisory detailing patches for seven plugin vulnerabilities, including high-severity path traversal and Stored Cross-Site Scripting (XSS) flaws. Administrators mus ... Read more
The following table lists the changes that have been made to the
CVE-2026-42521 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 06, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:jenkins:matrix_authorization_strategy:*:*:*:*:*:jenkins:*:* versions from (including) 2.1 up to (excluding) 3.2.10 *cpe:2.3:a:jenkins:matrix_authorization_strategy:2.0:beta1:*:*:*:jenkins:*:* *cpe:2.3:a:jenkins:matrix_authorization_strategy:2.0:beta2:*:*:*:jenkins:*:* *cpe:2.3:a:jenkins:matrix_authorization_strategy:2.0:beta3:*:*:*:jenkins:*:* Added Reference Type Jenkins Project: https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3676 Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 29, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-502 -
New CVE Received by [email protected]
Apr. 29, 2026
Action Type Old Value New Value Added Description Jenkins Matrix Authorization Strategy Plugin 2.0-beta-1 through 3.2.9 (both inclusive) invokes parameterless constructors of classes specified in configuration when deserializing inheritance strategies, without restricting the classes that can be instantiated, allowing attackers with Item/Configure permission to instantiate arbitrary types, which may lead to information disclosure or other impacts depending on the classes available on the classpath. Added Reference https://www.jenkins.io/security/advisory/2026-04-29/#SECURITY-3676