CVE-2026-33001: Jenkins core Jenkins Has A Link Following Vulnerability

HIGH
Advisory Identifier: GHSA-r6qv-frpc-q66c
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CVSS 8.8
CWE-59 CWE-61
Published
Advisory Summary

CVE-2026-33001 is a HIGH (CVSS 8.8) jenkins has a link following vulnerability (CWE-59: Improper Link Resolution Before File Access ('Link Following')) affecting Jenkins core libraries in the Maven ecosystem. The issue involves jenkins has a link following vulnerability allows arbitrary file creation. Remediation is available by upgrading affected packages to version 2.555.

CVE-2026-33001 at a Glance

CVE Identifier CVE-2026-33001
GHSA Identifier GHSA-r6qv-frpc-q66c
Severity HIGH
CVSS v3.1 Base Score 8.8
CWE Classification CWE-59: Improper Link Resolution Before File Access ('Link Following')
Affected Product Jenkins core
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-33001

To remediate this vulnerability, upgrade all affected Jenkins core dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.jenkins-ci.main:jenkins-core fixed: 2.555 
<dependency>
    <groupId>org.jenkins-ci.main</groupId>
    <artifactId>jenkins-core</artifactId>
    <version>2.555</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.jenkins-ci.main

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-33001, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.jenkins-ci.main

Analyze the terminal output to locate any version of Jenkins core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.555), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.jenkins-ci.main command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-59: Improper Link Resolution Before File Access ('Link Following'), where the product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. In Jenkins core, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Jenkins 2.554 and earlier, LTS 2.541.2 and earlier does not safely handle symbolic links during the extraction of .tar and .tar.gz archives, allowing crafted archives to write files to arbitrary locations on the filesystem, restricted only by file system access permissions of the user running Jenkins. This can be exploited to deploy malicious scripts or plugins on the controller by attackers with Item/Configure permission, or able to control agent processes.

CVE-2026-33001 Affected Jenkins core Versions

1 component(s)
Fixed Versions:
2.555
Product / Package Ecosystem Affected Versions Fixed Version
org.jenkins-ci.main:jenkins-core
maven/org.jenkins-ci.main/jenkins-core
Maven
< 2.555
2.555

References

NVD — CVE-2026-33001 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33001
Security Fix Commit FIX COMMIT
https://github.com/jenkinsci/jenkins/commit/6dc99937605d5bddfeaae43a4cd14c2571e23adc
Jenkins core Source Repository REPOSITORY
https://github.com/jenkinsci/jenkins
Jenkins core Release RELEASE
https://github.com/jenkinsci/jenkins/releases/tag/jenkins-2.555
Jenkins core Security Information SECURITY
https://www.jenkins.io/security/advisory/2026-03-18/#SECURITY-3657

Frequently Asked Questions

What is CVE-2026-33001?
CVE-2026-33001 is a security vulnerability in Jenkins core involving Jenkins has a link following vulnerability allows arbitrary file creation under CWE-59: Improper Link Resolution Before File Access ('Link Following').
Which Jenkins core versions are affected?
Affected versions include releases prior to 2.555 across affected packages: org.jenkins-ci.main:jenkins-core.
What version fixes CVE-2026-33001?
Upgrading to 2.555 (or the latest patched release for your respective branch) resolves the vulnerability.
Is jenkins-core affected?
Yes, org.jenkins-ci.main:jenkins-core is affected in releases prior to 2.555. Upgrade your dependency to 2.555 or later.
What is the CVSS score of CVE-2026-33001?
CVE-2026-33001 has a CVSS v3.1 base score of 8.8 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-33001?
CVE-2026-33001 is classified under CWE-59: Improper Link Resolution Before File Access ('Link Following') (The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.).
How can I check Maven dependencies for CVE-2026-33001?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.jenkins-ci.main'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-r6qv-frpc-q66c",
  "modified" : "2026-03-19T23:22:20Z",
  "published" : "2026-03-18T18:31:16Z",
  "aliases" : [ "CVE-2026-33001" ],
  "summary" : "Jenkins has a link following vulnerability allows arbitrary file creation",
  "details" : "Jenkins 2.554 and earlier, LTS 2.541.2 and earlier does not safely handle symbolic links during the extraction of .tar and .tar.gz archives, allowing crafted archives to write files to arbitrary locations on the filesystem, restricted only by file system access permissions of the user running Jenkins.\nThis can be exploited to deploy malicious scripts or plugins on the controller by attackers with Item/Configure permission, or able to control agent processes.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.jenkins-ci.main:jenkins-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.555"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.554"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33001"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jenkinsci/jenkins/commit/6dc99937605d5bddfeaae43a4cd14c2571e23adc"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/jenkinsci/jenkins"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/jenkinsci/jenkins/releases/tag/jenkins-2.555"
  }, {
    "type" : "WEB",
    "url" : "https://www.jenkins.io/security/advisory/2026-03-18/#SECURITY-3657"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-59", "CWE-61" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-19T12:46:21Z",
    "nvd_published_at" : "2026-03-18T16:16:28Z"
  }
}