A recently discovered vulnerability (CVE-2023-30522) in Jenkins Fogbugz Plugin 2.2.17 and earlier versions allows attackers with unauthorized access to trigger builds of jobs without proper permissions. This security risk arises from a missing permission check in the plugin's code, potentially exposing sensitive data and enabling bad actors to have direct access to your build servers.

How Does This Vulnerability Affect You?

If you are using a version of Jenkins Fogbugz Plugin (2.2.17 and earlier), your instance is susceptible to this vulnerability. This means attackers who have obtained 'Item/Read' permission can launch builds of jobs specified in a 'jobname' request parameter without the need for further permissions.

Exploit Details

The vulnerability arises from the lack of a permission check in a specific part of the source code of Jenkins Fogbugz Plugin. This code snippet, reproduced below, demonstrates this issue:

if (fogbugzJobName != null) {
   Job<?, ?> job = Jenkins
              .getInstanceOrNull()
              .getItemByFullName(fogbugzJobName, Job.class);
   if (job != null) {
       job.scheduleBuild(new Cause.UserIdCause());
   }
}

Within this code snippet, you can see that the scheduleBuild() function is called directly without performing a permission check for the current user. This allows attackers with 'Item/Read' permission to trigger builds consistently, thereby bypassing the necessary security protocols.

Immediate Action Needed

To protect your Jenkins Fogbugz Plugin implementation from this security vulnerability, users of version 2.2.17 and earlier should take the following steps:

Update your Jenkins Fogbugz Plugin to the latest version containing the fix for this vulnerability

- Download the latest version from https://plugins.jenkins.io/fogbugz/

2. If possible, implement additional monitoring and logging strategies to track access attempts and identify unauthorized users misusing the 'Item/Read' permission.

3. Review your Jenkins instance permissions and ensure that 'Item/Read' permission is granted only to trustworthy and authorized users and remove permissions from users who do not require such access.

Original References and Additional Information

- Official CVE information: https://www.jenkins.io/security/advisory/2023-02-18/
- Jenkins Security Advisory: https://www.jenkins.io/security/advisory/2023-02-18/#SECURITY-1347 (provides details regarding the vulnerability, CVSS score, and affected versions).
- Jenkins Fogbugz Plugin Changelog: https://plugins.jenkins.io/ui/search/?q=Fogbugz (track updates and fixes related to the plugin).

Important Reminder

Always keep your Jenkins instance and plugins up to date with the most recent security fixes and updates to avoid potential security risks. Regularly review permissions and access control configurations, and follow recommended best practices for securing your systems.

Stay vigilant, and make sure to spread the word by sharing this information with fellow Jenkins Fogbugz Plugin users or administrators. Together, we can ensure that our Jenkins implementations are more secure and resistant to exploitation.

Timeline

Published on: 04/12/2023 18:15:00 UTC
Last modified on: 04/20/2023 20:12:00 UTC