Full Report
Jenkins security advisory (AV26-578)
Analysis Summary
# Vulnerability: Critical Security Updates for Jenkins Core (AV26-578)
## CVE Details
*Note: While the specific CVE IDs were not enumerated in the high-level summary provided, Jenkins Security Advisory 2026-06-10 typically covers multiple vulnerabilities ranging from Critical to Low.*
- **CVE ID:** [Pending specific CVEs from hxxps[://]www[.]jenkins[.]io/security/advisory/2026-06-10/]
- **CVSS Score:** Up to 9.8 (Critical) - *Estimated based on standard Jenkins Core advisory patterns.*
- **CWE:** Commonly includes CWE-502 (Deserialization), CWE-79 (XSS), or CWE-862 (Missing Authorization).
## Affected Systems
- **Products:** Jenkins (Weekly and Long-Term Support/LTS)
- **Versions:**
- Jenkins Weekly: 2.567 and prior
- Jenkins LTS: 2.555.2 and prior
- **Configurations:** Default installations and specific plugin configurations integrated with Jenkins core.
## Vulnerability Description
This advisory addresses multiple security flaws within the Jenkins controller. Historically, these advisories address issues related to unauthorized access, remote code execution (RCE) via improper input validation, or cross-site scripting (XSS) in the management UI. These flaws reside in the core architecture responsible for handling user requests and pipeline orchestration.
## Exploitation
- **Status:** PoC availability is expected shortly after disclosure; vulnerability is likely not yet exploited in the wild at the time of the advisory.
- **Complexity:** Low to Medium (Depending on the specific CVE)
- **Attack Vector:** Network (Typically exploitable via HTTP/HTTPS)
## Impact
- **Confidentiality:** High (Potential for unauthorized data access)
- **Integrity:** High (Potential for unauthorized modification of build configurations)
- **Availability:** High (Potential for Denial of Service or system takeover)
## Remediation
### Patches
The following versions address the identified vulnerabilities:
- **Jenkins weekly:** Update to version **2.568** or later.
- **Jenkins LTS:** Update to version **2.555.3** or later.
### Workarounds
- Restrict network access to the Jenkins controller to trusted IP addresses only.
- Disable "Allow anonymous read access" in Global Security settings.
- Ensure "Enable Proxy Compatibility" is managed correctly if using reverse proxies.
## Detection
- **Indicators of Compromise:** Unusual login attempts in `hudson.security` logs; unexpected modifications to `config.xml` files; presence of unauthorized .jar files in the `plugins` directory.
- **Detection methods and tools:**
- Use the **Jenkins Health Advisor by CloudBees** to identify outdated instances.
- Monitor web server logs for suspicious POST requests to `/ajax` or `/script` endpoints.
## References
- hxxps[://]www[.]jenkins[.]io/security/advisory/2026-06-10/
- hxxps[://]www[.]jenkins[.]io/security/advisories/
- hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/jenkins-security-advisory-av26-578