Description
Jenkins FilePath.untarFrom() does not validate symlink targets when extracting TAR archives, allowing an attacker with Item/Configure permission to create symlinks from a workspace to arbitrary files on the Jenkins controller. This issue remains exploitable in versions patched for CVE-2026-33001 and CVE-2026-70427. An attacker can use this to read sensitive files from $JENKINS_HOME, including Jenkins cryptographic keys and stored credentials. Jenkins 2.576 is additionally affected by a Unicode zero-width character bypass of the blank-name validation introduced by CVE-2026-70427.
CVSS breakdown
CVSS 4.0
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
Low
User Interaction
None
Confidentiality (Vulnerable System)
High
Integrity (Vulnerable System)
High
Availability (Vulnerable System)
High
Confidentiality (Subsequent System)
High
Integrity (Subsequent System)
High
Availability (Subsequent System)
High
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Jenkins Project / Jenkins0 – 2.555.3
- Jenkins Project / Jenkins
- Jenkins Project / Jenkins1.0 – 2.576
- Jenkins Project / Jenkins1.0 – 2.568.2
- Jenkins Project / Jenkins1.0 – 2.577
Updated 13m ago · 8 sources