CVE-2017-1000353 : Security Advisory and Response

Jenkins versions prior to 2.56 and 2.46.1 LTS and earlier are susceptible to a remote code execution vulnerability. Attackers can exploit this flaw by sending a serialized Java

SignedObject

object to the Jenkins CLI, bypassing the existing protection mechanisms.

Understanding CVE-2017-1000353

This CVE involves a critical vulnerability in Jenkins that allows remote code execution without authentication.

What is CVE-2017-1000353?

Jenkins versions 2.56 and earlier, as well as 2.46.1 LTS and earlier, are vulnerable to unauthenticated remote code execution. The flaw enables attackers to execute code remotely by manipulating the Jenkins CLI.

The Impact of CVE-2017-1000353

The vulnerability permits attackers to execute arbitrary code on the Jenkins server, potentially leading to unauthorized access, data breaches, and system compromise.

Technical Details of CVE-2017-1000353

This section provides in-depth technical insights into the vulnerability.

Vulnerability Description

The flaw allows attackers to send a serialized Java

SignedObject

object to the Jenkins CLI, which is deserialized using a new

ObjectInputStream

, bypassing the existing protection mechanisms.

Affected Systems and Versions

Jenkins versions prior to 2.56
Jenkins 2.46.1 LTS and earlier

Exploitation Mechanism

Attackers exploit the vulnerability by sending a malicious serialized Java object to the Jenkins CLI, enabling them to execute arbitrary code remotely.

Mitigation and Prevention

Protect your systems from CVE-2017-1000353 with the following measures:

Immediate Steps to Take

Update Jenkins to version 2.56 or later.
Apply the necessary security patches provided by Jenkins.

Long-Term Security Practices

Regularly monitor and update Jenkins to the latest versions.
Implement network segmentation to limit the impact of potential security breaches.

Patching and Updates

Jenkins has addressed the vulnerability by adding

SignedObject

to the blacklist and backporting the new HTTP CLI protocol from Jenkins 2.54 to LTS 2.46.2.
The remoting-based CLI protocol (using Java serialization) has been deprecated and disabled by default.