CyberSecBulletin
CVE-2026-33001NVD status: Modified

Jenkins: Improper Link Resolution Before File Access

Published Updated By the CyberSecBulletin desk

CVE-2026-33001 is a high-severity improper link resolution before file access vulnerability in Jenkins, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 2.26% chance of exploitation within 30 days, higher than 83% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Jenkins you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on jenkins.io for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Jenkins ProjectJenkinsNot specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.12Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.13Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.14Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.15Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.16Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.17Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.18Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.19Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.20Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.21Not specified in the recordNot stated
Red HatRed Hat Developer HubNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCISA (ADP)
CVSS 3.18.8HighCNA

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Link Resolution Before File Access

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 developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Jenkins

All Jenkins vulnerabilities

Recent Improper Link Resolution Before File Access vulnerabilities

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