CVE-2026-70426
Description
A flaw was found in Jenkins Remoting. This vulnerability allows agent processes, code running on agents, and attackers with Agent/Connect permission to bypass the JEP-200 deserialization filter. This bypass occurs because the filter is not applied to classes resolved through a fallback path in the Remoting deserialization implementation. Successful exploitation could lead to arbitrary code execution on the Jenkins controller.
Statement
This Important flaw in Jenkins Remoting allows authenticated attackers or compromised agent processes to execute arbitrary code on the Jenkins controller. The vulnerability stems from an incomplete deserialization filter bypass, enabling full compromise of the Jenkins environment. This impacts Red Hat OpenShift Developer Tools & Services deployments that utilize Jenkins agents, as it could lead to unauthorized control over the build and deployment infrastructure.
Agent traffic in Red Hat OpenShift Developer Tools is restricted to a cluster's internal pod network which reduces the attack vector from Network to Adjacent.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.3 | N/A | 9 |
| Attack Vector | Adjacent Network | N/A | Network |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Changed | N/A | Changed |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
Frequently Asked Questions
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