CVE-2024-23897: Jenkins Command Line Interface (CLI) Path Traversal Vulnerability

Should you act?

Exploited: patch now if you run it

CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Yes, if you run Jenkins Jenkins Command Line Interface (CLI). CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2024-08-19, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2024-09-09; treat that as the outer limit, not the target. CISA also lists it as known to be used in ransomware campaigns.
• EPSS 100.0%, percentile 100.0: FIRST’s model estimates a 100.0% chance of exploitation activity in the next 30 days, higher than 100.0% of all scored CVEs (very high). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes org.jenkins-ci.main:jenkins-core (Maven) >= 1.606, <= 2.426.2, fixed in 2.426.3; org.jenkins-ci.main:jenkins-core (Maven) = 2.441, fixed in 2.442; org.jenkins-ci.main:jenkins-core (Maven) >= 2.427, < 2.440.1, fixed in 2.440.1. Check your lockfile, including transitive dependencies.
• Editorial verdict: Act now. Jenkins CLI Arbitrary File Read (CVE-2024-23897) — An unpatched Jenkins controller reachable by untrusted users leaks files and secrets that can lead to full takeover; upgrade now or disable the CLI.

What it is

Jenkins 2.441 and earlier, LTS 2.426.2 and earlier does not disable a feature of its CLI command parser that replaces an '@' character followed by a file path in an argument with the file's contents, allowing unauthenticated attackers to read arbitrary files on the Jenkins controller file system.

From the GitHub advisory

Jenkins has a built-in command line interface (CLI) to access Jenkins from a script or shell environment.

Jenkins uses the args4j library to parse command arguments and options on the Jenkins controller when processing CLI commands. This command parser has a feature that replaces an @ character followed by a file path in an argument with the file’s contents (expandAtFiles). This feature is enabled by default and Jenkins 2.441 and earlier, LTS 2.426.2 and earlier does not disable it.

This allows attackers to read arbitrary files on the Jenkins controller file system using the default character encoding of the Jenkins controller process.

Attackers with Overall/Read permission can read entire files.

Attackers without Overall/Read permission can read the first few lines of files. The number of lines that can be read depends on available CLI commands. As of publication of this advisory, the Jenkins security team has found ways to read the first three lines of files in recent releases of Jenkins without having any plugins installed, and has not identified any plugins that would increase this line count.

CISA’s summary

Jenkins Command Line Interface (CLI) contains a path traversal vulnerability that allows attackers limited read access to certain files, which can lead to code execution.

Weakness type: CWE-27, CWE-22.

Product: Jenkins Jenkins Command Line Interface (CLI) · Assigned by: jenkins · Published: 2024-01-24

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: none (no login)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: added 2024-08-19; federal due date 2024-09-09. Known ransomware use: Known.
• CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
• CISA SSVC assessment: exploitation active, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 100.00% probability of exploitation activity in the next 30 days; percentile 100.0.

Timeline

• 2024-01-24 — CVE record published by jenkins
• 2024-01-24 — GitHub-reviewed advisory GHSA-6f9g-cxwr-q5jr published (critical)
• 2024-01-24 — erroneo.us brief: Jenkins CLI Arbitrary File Read (CVE-2024-23897)
• 2024-08-19 — Added to CISA’s Known Exploited Vulnerabilities catalog
• 2024-09-09 — CISA remediation deadline for US federal agencies
• 2025-10-21 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. Jenkins Security Advisory 2024-01-24 jenkins.io

Vulnerability records

1. GitHub Advisory GHSA-6f9g-cxwr-q5jr github.com
2. CVE.org record CVE-2024-23897 cve.org
3. NVD entry CVE-2024-23897 nvd.nist.gov

Government

1. CISA Known Exploited Vulnerabilities catalog entry cisa.gov

Other references from the CVE record and advisory

1. sonarsource.com sonarsource.com
2. openwall.com openwall.com
3. packetstormsecurity.com packetstormsecurity.com
4. packetstormsecurity.com packetstormsecurity.com
5. vicarius.io vicarius.io
6. jenkins.io jenkins.io
7. github.com github.com

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