Multiple PoC exploits released for Jenkins flaw CVE-2024
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2024-23897 | Path Traversal in Jenkins CLI Allows File Read and Code Execution CVE-2024-23897 is a path traversal flaw in the Jenkins Command Line Interface (CLI), the built-in remote-access component of the Jenkins automation server. It is triggered when an attacker submits crafted CLI requests to a Jenkins controller, causing the CLI to resolve paths outside the intended directory and return file contents. The attacker gains limited read access to files on the controller, which can be leveraged toward code execution. Any organization running a Jenkins controller with the CLI enabled — the CLI ships with Jenkins and is commonly left on, including on internet-facing build servers — is affected. Exploitation is confirmed in the wild: the flaw is on the CISA Known Exploited Vulnerabilities catalog (added 2024-08-19) with known ransomware use, and EPSS puts its 30-day exploitation probability at 100%. Do: Upgrade Jenkins controllers to a fixed release per the vendor advisory, or apply the KEV-required mitigations — notably disabling or restricting access to the CLI — and discontinue use if mitigations are unavailable. Prioritize internet-facing Jenkins instances given known ransomware use, verify your running controller version against the advisory's fixed versions, and hunt for anomalous CLI request activity and signs of file-read reconnaissance on the controller host. | 9.8 | 100% | KEV ransomware PoC ×3 |
| largetens of thousands of internet-exposed Jenkins controllers, plausibly 100,000+ total installations |
Full article427 words · extracted from securityaffairs.com · click to collapse
Multiple proof-of-concept (PoC) exploits for recently disclosed critical Jenkins vulnerability CVE-2024-23897 have been released.
Researchers warn that several proof-of-concept (PoC) exploits targeting the recently disclosed critical Jenkins vulnerability, CVE-2024-23897, have been made public.
Jenkins is the most popular open source automation server, it is maintained by CloudBees and the Jenkins community. The automation server supports developers build, test and deploy their applications, it has hundreds of thousands of active installations worldwide with more than 1 million users.
The maintainers of the open-source platform have addressed nine security vulnerabilities, including a critical flaw, tracked as CVE-2024-23897, that could lead to remote code execution (RCE). The vulnerability was reported by the researcher Yaniv Nizry from Sonar who wrote a detailed analysis of the issue.
Jenkins has a built-in command line interface (CLI) to access the platform from a script or shell environment. The open-source software uses the args4j library to parse CLI command arguments and options on the Jenkins controller. The parser uses a functionality that replaces the ‘@’ character followed by a file path in an argument with the content of the file (‘expandAtFiles’). This feature is enabled by default and Jenkins 2.441 and earlier, LTS 2.426.2 and earlier does not disable it.
An attacker can abuse the default character encoding of the Jenkins controller process to read arbitrary files on the controller file system.
An attacker with “Overall/Read” permission can read entire files, while an attacker without it can read the first three lines of the files depending on the CLI commands.
The maintainers pointed out that exploiting this flaw makes it possible to read binary files containing cryptographic keys used for various Jenkins features, even with some limitations.
The popular cyberesecurity researcher Florian Roth warned of a couple of weaponized PoC exploits have been released.
— JFrog Security (@JFrogSecurity) January 28, 2024Critical CVE-2024-23897 in Jenkins allows unauthenticated attackers to partially leak files and authenticated attackers to leak entire files – which can lead to RCE in many cases!
Weaponized exploits are already published – https://t.co/j0Ko58YcI4
For remediation – https://t.co/8hCma88vGf
The researcher German Fernandez warned of a massive exploitation of the vulnerability, querying Shodan, he found more than 75000 internet-facing instances.
— Germán Fernández (@1ZRR4H) January 26, 2024🚨 CVE-2024-23897: Unauthenticated Arbitrary File Read vulnerability could lead to RCE on Jenkins servers.
▪ Exploits are already available.https://t.co/xreXZ88kIZ
The availability of “PoC exploits” will cause several threat actors to start exploiting the vulnerability in attacks in the wild.
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