9.4
CRITICAL
CVSS 4.0
CVE-2026-19429
Jenkins - FilePath.untarFrom() Symlink Target Validation Bypass and Blank-Name Check Bypass (Arbitrary File Read)
Overview
Description
Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
Details
INFO
Published Date :
Aug. 10, 2026, 1:17 p.m.
Last Modified :
Aug. 13, 2026, 12:17 p.m.
Remotely Exploit :
Yes !
Source :
309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework
for assessing the severity of vulnerabilities in software and systems.
We collect and displays CVSS scores from various sources for each CVE.
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c | ||||
| CVSS 4.0 | CRITICAL | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c | ||||
| CVSS 4.0 | HIGH | 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c |
Solution
Update Jenkins to a version that fully addresses arbitrary file read vulnerabilities.
- Update Jenkins to the latest stable release.
- Apply vendor-supplied patches for Jenkins.
- Review Jenkins security advisories.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-19429 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-19429 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 13, 2026
Action Type Old Value New Value Changed 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. Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority. Removed CVSS V4.0 TuranSec: AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Removed CVSS V3.1 TuranSec: AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Removed CWE TuranSec: CWE-59 Removed CWE TuranSec: CWE-184 Removed Reference TuranSec: https://github.com/jenkinsci/jenkins Removed Reference TuranSec: https://www.jenkins.io/security/advisory/2026-03-18/#SECURITY-3657 Removed Reference TuranSec: https://www.jenkins.io/security/advisory/2026-08-05/ Removed Affected [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'versions': [{'status': 'affected', 'version': '1.0', 'versionType': 'weekly', 'lessThanOrEqual': '2.577'}, {'status': 'affected', 'version': '1.0', 'versionType': 'LTS', 'lessThanOrEqual': '2.568.2'}], 'defaultStatus': 'affected'}] -
CVE Rejected by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 13, 2026
Action Type Old Value New Value -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 13, 2026
Action Type Old Value New Value Changed Affected [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'versions': [{'status': 'affected', 'version': '1.0', 'versionType': 'weekly', 'lessThanOrEqual': '2.576'}, {'status': 'affected', 'version': '1.0', 'versionType': 'LTS', 'lessThanOrEqual': '2.568.2'}], 'defaultStatus': 'affected'}] [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'versions': [{'status': 'affected', 'version': '1.0', 'versionType': 'weekly', 'lessThanOrEqual': '2.577'}, {'status': 'affected', 'version': '1.0', 'versionType': 'LTS', 'lessThanOrEqual': '2.568.2'}], 'defaultStatus': 'affected'}] Changed Description 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. 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. -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 11, 2026
Action Type Old Value New Value Changed Affected [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'defaultStatus': 'affected'}] [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'versions': [{'status': 'affected', 'version': '1.0', 'versionType': 'weekly', 'lessThanOrEqual': '2.576'}, {'status': 'affected', 'version': '1.0', 'versionType': 'LTS', 'lessThanOrEqual': '2.568.2'}], 'defaultStatus': 'affected'}] Changed Description Jenkins FilePath.untarFrom() in all versions, including those with the CVE-2026-33001 and CVE-2026-70427 patches applied, contains two distinct symlink validation weaknesses that independently allow arbitrary file read. 1. SYMLINK TARGET NOT VALIDATED (all versions): The CVE-2026-33001 fix enforces that the symlink file is created within the workspace boundary, but the symlink target — the path returned by te.getLinkName() and passed directly to symlinkTo() — is never validated and may point to any path on the controller filesystem. 2. BLANK-NAME CHECK BYPASS via Unicode (Jenkins 2.576): The CVE-2026-70427 patch added a blank-name check using Java's String.isBlank() to reject symlinks with empty names. However, String.isBlank() does not recognize Unicode zero-width characters (U+200B ZERO WIDTH SPACE, U+200C ZERO WIDTH NON-JOINER, U+200D ZERO WIDTH JOINER, U+2060 WORD JOINER, U+00AD SOFT HYPHEN) as whitespace. A tar entry named with any of these characters passes the blank-name check and results in a symlink with an invisible name pointing to an arbitrary target. An attacker with Item/Configure permission can configure a job to extract a malicious .tar or .tar.gz archive. When FilePath.untarFrom() processes the archive, it creates symlinks inside the workspace that resolve to arbitrary controller paths. By targeting the entire $JENKINS_HOME/secrets/ directory — including master.key, hudson.util.Secret, and credentials.xml — an attacker can exfiltrate all Jenkins cryptographic material and offline-decrypt all {AQA...}-format credential entries, exposing every password, API key, cloud provider secret, and SSH private key stored in Jenkins. 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Removed CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Removed CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added Reference https://www.jenkins.io/security/advisory/2026-08-05/ -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 11, 2026
Action Type Old Value New Value Changed Description Jenkins FilePath.untarFrom() in all versions, including those with the CVE-2026-33001 patch applied, validates symlink destinations but not targets. The CVE-2026-33001 fix enforces that the symlink file is created within the workspace boundary, but the symlink target — the path returned by te.getLinkName() and passed directly to symlinkTo() — is never validated and may point to any path on the controller filesystem. An attacker with Item/Configure permission can configure a job to extract a malicious .tar or .tar.gz archive via a tool installer or custom build step. When FilePath.untarFrom() processes the archive, it creates symlinks inside the workspace that resolve to arbitrary controller paths. By targeting the entire $JENKINS_HOME/secrets/ directory — including master.key, hudson.util.Secret, hudson.model.Secrets.xml, and any other files present — an attacker can exfiltrate all Jenkins cryptographic material through the workspace viewer (GET /job/{name}/ws/) or build artifacts. Combined with credentials.xml and per-user config.xml files, this enables offline AES-128 decryption of all {AQA...}-format credential entries, exposing in plaintext every password, API key, cloud provider secret, and SSH private key stored in the Jenkins credential store — compromising all downstream systems those credentials protect. Jenkins FilePath.untarFrom() in all versions, including those with the CVE-2026-33001 and CVE-2026-70427 patches applied, contains two distinct symlink validation weaknesses that independently allow arbitrary file read. 1. SYMLINK TARGET NOT VALIDATED (all versions): The CVE-2026-33001 fix enforces that the symlink file is created within the workspace boundary, but the symlink target — the path returned by te.getLinkName() and passed directly to symlinkTo() — is never validated and may point to any path on the controller filesystem. 2. BLANK-NAME CHECK BYPASS via Unicode (Jenkins 2.576): The CVE-2026-70427 patch added a blank-name check using Java's String.isBlank() to reject symlinks with empty names. However, String.isBlank() does not recognize Unicode zero-width characters (U+200B ZERO WIDTH SPACE, U+200C ZERO WIDTH NON-JOINER, U+200D ZERO WIDTH JOINER, U+2060 WORD JOINER, U+00AD SOFT HYPHEN) as whitespace. A tar entry named with any of these characters passes the blank-name check and results in a symlink with an invisible name pointing to an arbitrary target. An attacker with Item/Configure permission can configure a job to extract a malicious .tar or .tar.gz archive. When FilePath.untarFrom() processes the archive, it creates symlinks inside the workspace that resolve to arbitrary controller paths. By targeting the entire $JENKINS_HOME/secrets/ directory — including master.key, hudson.util.Secret, and credentials.xml — an attacker can exfiltrate all Jenkins cryptographic material and offline-decrypt all {AQA...}-format credential entries, exposing every password, API key, cloud provider secret, and SSH private key stored in Jenkins. Added CWE CWE-184 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 10, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-19429', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-10T15:34:41.496974Z'} -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 10, 2026
Action Type Old Value New Value Changed Description Jenkins FilePath.untarFrom() (all versions) validates symlink destinations but not targets, bypassing CVE-2026-33001. Any user with Item/Build access triggers tar extraction via POST /job/{name}/build, writing persistent symlinks into the tool cache. Symlinks to secrets/master.key, hudson.util.Secret, credentials.xml, and users/*/config.xml read via GET /job/{name}/lastBuild/consoleText enable offline AES decryption of all credentials and admin API tokens without bcrypt cracking, achieving RCE. Jenkins FilePath.untarFrom() in all versions, including those with the CVE-2026-33001 patch applied, validates symlink destinations but not targets. The CVE-2026-33001 fix enforces that the symlink file is created within the workspace boundary, but the symlink target — the path returned by te.getLinkName() and passed directly to symlinkTo() — is never validated and may point to any path on the controller filesystem. An attacker with Item/Configure permission can configure a job to extract a malicious .tar or .tar.gz archive via a tool installer or custom build step. When FilePath.untarFrom() processes the archive, it creates symlinks inside the workspace that resolve to arbitrary controller paths. By targeting the entire $JENKINS_HOME/secrets/ directory — including master.key, hudson.util.Secret, hudson.model.Secrets.xml, and any other files present — an attacker can exfiltrate all Jenkins cryptographic material through the workspace viewer (GET /job/{name}/ws/) or build artifacts. Combined with credentials.xml and per-user config.xml files, this enables offline AES-128 decryption of all {AQA...}-format credential entries, exposing in plaintext every password, API key, cloud provider secret, and SSH private key stored in the Jenkins credential store — compromising all downstream systems those credentials protect. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Removed CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Removed CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added Reference https://www.jenkins.io/security/advisory/2026-03-18/#SECURITY-3657 Removed Reference https://www.jenkins.io/security/advisories/2026-03-19/ -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 10, 2026
Action Type Old Value New Value Changed Description Jenkins FilePath.untarFrom() (all versions) validates symlink destinations but not targets, bypassing CVE-2026-33001. Any user with Item/Build access can trigger extraction of a malicious tar via POST /job/{name}/build, planting symlinks to secrets/master.key, secrets/hudson.util.Secret, and credentials.xml. Files are read via GET /job/{name}/lastBuild/consoleText. These three files enable offline AES decryption of all stored Jenkins credentials, escalating to admin access and RCE. Jenkins FilePath.untarFrom() (all versions) validates symlink destinations but not targets, bypassing CVE-2026-33001. Any user with Item/Build access triggers tar extraction via POST /job/{name}/build, writing persistent symlinks into the tool cache. Symlinks to secrets/master.key, hudson.util.Secret, credentials.xml, and users/*/config.xml read via GET /job/{name}/lastBuild/consoleText enable offline AES decryption of all credentials and admin API tokens without bcrypt cracking, achieving RCE. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Removed CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N -
CVE Modified by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 10, 2026
Action Type Old Value New Value Changed Description An incomplete patch for CVE-2026-33001 in Jenkins Project Jenkins through LTS 2.555.3 allows an authenticated remote attacker with Item/Configure permission to read arbitrary files on the Jenkins controller filesystem via a crafted tar archive. The CVE-2026-33001 security update validates symlink destinations during tar extraction in FilePath.java but does not validate symlink targets; a symlink whose location is inside the workspace can still point to arbitrary paths outside it, enabling disclosure of any file readable by the Jenkins process user, including secrets/master.key, credentials.xml, and other sensitive configuration files. Jenkins FilePath.untarFrom() (all versions) validates symlink destinations but not targets, bypassing CVE-2026-33001. Any user with Item/Build access can trigger extraction of a malicious tar via POST /job/{name}/build, planting symlinks to secrets/master.key, secrets/hudson.util.Secret, and credentials.xml. Files are read via GET /job/{name}/lastBuild/consoleText. These three files enable offline AES decryption of all stored Jenkins credentials, escalating to admin access and RCE. -
New CVE Received by 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c
Aug. 10, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Jenkins Project', 'product': 'Jenkins', 'defaultStatus': 'affected'}] Added Description An incomplete patch for CVE-2026-33001 in Jenkins Project Jenkins through LTS 2.555.3 allows an authenticated remote attacker with Item/Configure permission to read arbitrary files on the Jenkins controller filesystem via a crafted tar archive. The CVE-2026-33001 security update validates symlink destinations during tar extraction in FilePath.java but does not validate symlink targets; a symlink whose location is inside the workspace can still point to arbitrary paths outside it, enabling disclosure of any file readable by the Jenkins process user, including secrets/master.key, credentials.xml, and other sensitive configuration files. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-59 Added Reference https://github.com/jenkinsci/jenkins Added Reference https://www.jenkins.io/security/advisories/2026-03-19/
EPSS is a daily estimate of the probability of exploitation activity
being observed over the next 30 days. Following chart shows the EPSS
score history of the vulnerability.