6.5

CVE-2026-42521: jenkins project jenkins matrix authorization strategy plugin Deserialization of Untrusted Data

CVSS: 6.5v3.1MediumAnalyzed
AliasesCGA-3c7m-4464-x7g8CGA-7hq2-9m44-vc98CGA-8qp8-3j89-gr4m
Published 29-04-2026Last modified 29-04-2026
Open JSON

Vulnerability summary

CVE-2026-42521 is a medium (CVSS 6.5) Deserialization of Untrusted Data vulnerability in jenkins project jenkins matrix authorization strategy plugin. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.1% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.39%
0%100%
Low · +0.14 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-XF72-2F4W-2M5X

Timeline

  1. 29-04-2026
    PublishedVulnerability first disclosed.
  2. 29-04-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.39%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

+0.14 pp

From 0.25% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.39%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard11 products
  • jenkins-2-openjdk-21< 2.560-r1
  • jenkins-2-openjdk-25< 2.563-r0
  • jenkins-2.528-openjdk-17All versions (No fix recorded)
  • jenkins-2.528-openjdk-21All versions (No fix recorded)
  • jenkins-2.541< 2.541.3-r8
Wolfi2 products
  • jenkins-2-openjdk-21< 2.560-r1
  • jenkins-2-openjdk-25< 2.563-r0
Jenkins1 product
Jenkins project1 product
Org.jenkins-ci.plugins1 product
  • matrix-auth≥ 2.0-beta-1, < 3.2.10

5 vendors · 16 products

References

3 links