What is the CVSS score of CVE-2026-70444?

CVE-2026-70444 has a CVSS 3.1 base score of 4.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N. EPSS exploitation probability: 0.2%.

Which versions of Jenkins are affected by CVE-2026-70444?

Critical remote code execution vulnerabilities in Jenkins core and plugins (CVE-2026-70444) enable code execution on Jenkins controllers through multiple attack vectors; no public exploit identified…

How to fix or mitigate CVE-2026-70444?

Within 24 hours: Audit your Jenkins deployment to identify all connected agents and users with Agent/Connect or build permissions; inventory systems running Remoting plugin version 3384.v60d89463d9e0 or earlier. Within 7 days: Implement network segmentation to restrict agent-to-controller communication to trusted networks only, disable or isolate agents over the public internet, and audit recent build logs for anomalous activity or unexpected deserialization errors. Within 30 days: Monitor Jenkins security advisories for vendor patches and develop an upgrade strategy; consider temporary measures such as restricting Jenkins jobs to controller-only execution and enforcing multi-factor authentication for administrative access until patches are released.

Jenkins CVE-2026-70444

EUVD-2026-53538 MEDIUM

Protection Mechanism Failure (CWE-693)

2026-08-05

GHSA-w5cj-vfc7-9rjq

Information Disclosure Gitlab Jenkins

4.3

CVSS 3.1 · Vendor

Severity by source

Vendor (CNA) PRIMARY

4.3 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

vuln.today AI

9.9 CRITICAL

Network vector via Remoting channel; PR:L for required Agent/Connect permission; scope change from agent to controller with full RCE impact.

3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Primary rating from Vendor (CNA).

CVSS VectorVendor

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Lifecycle Timeline

CVSS changed

Aug 05, 2026 - 20:22 NVD

4.3 (MEDIUM)

Analysis Generated

Aug 05, 2026 - 16:18 vuln.today

CVE Published

Aug 05, 2026 - 14:02 oss-security

CRITICAL

Description PRE-NVD

Disclosed via oss-security. NVD scoring and full description are pending.

Articles & Coverage 1

News Critical RCE via Deserialization Filter Bypass in Jenkins Remoting - CVE-2026-70444 Aug 05, 2026

AnalysisAI

Remote code execution and privilege escalation across Jenkins core and multiple plugins were disclosed in the 2026-08-05 security advisory, with the most critical issue being a JEP-200 deserialization filter bypass (CVE-2026-70426) in Remoting 3384.v60d89463d9e0 and earlier that allows agent processes or holders of Agent/Connect permission to execute arbitrary code on the Jenkins controller. Compounding this, two separate arbitrary file-write primitives (CVE-2026-70427 via malicious tar archives, CVE-2026-70428 via path traversal in file parameter names) independently enable code execution by writing into JENKINS_HOME/init.groovy.d/ or deploying rogue plugins. No public exploit code or CISA KEV listing was identified at time of analysis, but the attack surface spans both network-accessible agents and authenticated users with low-privilege build permissions.

Technical ContextAI

Jenkins relies on the Remoting library (agent.jar/remoting.jar) to pass serialized Java objects between the controller and build agents. JEP-200 introduced a class-filter allowlist to defend against deserialization gadget chains; CVE-2026-70426 reveals that a fallback resolution path inside the Remoting deserialization implementation bypasses this filter, exposing classes on the Jenkins core classpath that are absent from the pre-JEP-200 denylist. CVE-2026-70427 exploits deficient symbolic-link handling during tar/tar.gz extraction - a path-traversal class flaw (CWE-22 or CWE-59) that allows a crafted archive to write files outside the intended extraction directory. CVE-2026-70428 is a classic path-traversal (CWE-22) in file parameter name handling during build configuration. CVE-2026-70429 is a Unicode normalization inconsistency (CWE-178/CWE-176) between lowercasing used for canonical ID creation and String#equalsIgnoreCase used for comparisons, enabling homograph-style account impersonation. CVE-2026-70430 reflects an unsafe reflection/instantiation pattern (CWE-470) in the project naming strategy configuration. Multijob Plugin issues (CVE-2026-70431/70432) stem from unenforced Script Security Plugin integration (CWE-693) and missing CSRF token checks (CWE-352). HCL AppScan Plugin (CVE-2026-70433) lacks authorization checks on HTTP endpoints (CWE-862). Affected CPE strings include Jenkins core prior to 2.576 (weekly) and 2.568.2 (LTS), Multijob Plugin prior to 677.v7ffc23d6a_4c2, HCL AppScan Plugin prior to 1.8.4, and several additional plugins with unresolved issues.

RemediationAI

The primary fix for all core vulnerabilities is upgrading Jenkins to 2.576 (weekly) or Jenkins LTS 2.568.2, as announced in the advisory at https://www.jenkins.io/security/advisory/2026-08-05/. For the Multijob Plugin, upgrade to 677.v7ffc23d6a_4c2 or later. For HCL AppScan Plugin, upgrade to 1.8.4 or later. For External Workspace Manager Plugin, upgrade to 1.4.2; for SCM-Manager Plugin, upgrade to 1.12.1; for Webhook Secret Credentials Plugin, upgrade to 32.v09c9b_522f0a_8. The eleven plugins with unresolved issues (AWS CodeBuild, CodeSonar, Google Chat Notification, Horreum, Ivy Report, Parameterized Remote Trigger, Qualys Container Scanning Connector, Sauce OnDemand, Summary Display, Violation Comments to GitLab, XML Job to Job DSL) have no patch available at time of advisory publication; compensating controls include disabling the affected plugins via Manage Jenkins > Plugin Manager, restricting Item/Configure and Item/Build permissions to minimally trusted users, placing Jenkins behind an internal-only network perimeter to prevent external agent connections, and auditing JENKINS_HOME/init.groovy.d/ and JENKINS_HOME/plugins/ directories for unexpected files. Note that disabling plugins may break pipelines that depend on them.