CVE-2026-19429 (GCVE-0-2026-19429)

Vulnerability from cvelistv5 – Published: 2026-08-10 12:07 – Updated: 2026-08-11 07:23
VLAI
Title
Jenkins - FilePath.untarFrom() Symlink Target Validation Bypass and Blank-Name Check Bypass (Arbitrary File Read)
Summary
Jenkins FilePath.untarFrom() does not validate symlink targets in extracted TAR archives, even in versions patched for CVE-2026-33001 and CVE-2026-70427. An authenticated attacker with job configuration privileges can include a malicious archive in a build step that creates workspace symlinks pointing to arbitrary files on the Jenkins controller. By reading the secrets directory, the attacker obtains the cryptographic keys used to sign remember-me cookies, forges a valid administrator session cookie without any admin interaction, and gains access to the Script Console for remote code execution. Jenkins 2.576 is additionally affected by a bypass of the CVE-2026-70427 blank-name check via Unicode zero-width characters (U+200B, U+200C, U+200D, U+2060, U+00AD), which Java's String.isBlank() does not recognize as whitespace.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
  • CWE-184 - Incomplete List of Disallowed Inputs
Assigner
Impacted products
Vendor Product Version
Jenkins Project Jenkins Affected: 1.0 , ≤ 2.576 (weekly)
Affected: 1.0 , ≤ 2.568.2 (LTS)
Create a notification for this product.
Date Public
2026-08-10 12:00
Credits
Jamshed Yergashvoyev (CVE GUY | TuranSec)
Show details on NVD website

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