Bamboo Security Advisory 2017-12-13

Bamboo - Various vulnerabilities - CVE-2017-14589, CVE-2017-14590

Note: As of September 2014 we are no longer issuing binary bug patches, instead we create new maintenance releases for the major versions we are backporting.

Summary of Vulnerability

This advisory discloses critical severity security vulnerabilities which affects Bamboo. All versions of Bamboo before 6.1.6 (the fixed version for 6.1.x) and from 6.2.0 before 6.2.5 (the fixed version for 6.2.x) are affected by these vulnerabilities. 

Remote code execution through OGNL double evaluation (CVE-2017-14589)

Severity

Atlassian rates the severity level of this vulnerability as critical, according to the scale published in our Atlassian severity levels. The scale allows us to rank the severity as critical, high, moderate or low.

This is our assessment and you should evaluate its applicability to your own IT environment.

Description

It was possible for double OGNL evaluation in FreeMarker templates through Struts FreeMarker tags to occur. An attacker who has restricted administration rights to Bamboo or who hosts a website that a Bamboo administrator visits, is able to exploit this vulnerability to execute Java code of their choice on systems that run a vulnerable version of Bamboo.

All versions of Bamboo before 6.1.6 (the fixed version for 6.1.x) and from 6.2.0 before 6.2.5 (the fixed version for 6.2.x) are affected by this vulnerability. This issue can be tracked here: https://jira.atlassian.com/browse/BAM-18842

Acknowledgements

Atlassian would like to credit Sebastian Perez for reporting this issue to us.

Mitigation

This issue cannot be mitigated.

Argument injection in Mercurial repository handling (CVE-2017-14590)

Severity

Atlassian rates the severity level of this vulnerability as critical, according to the scale published in our Atlassian severity levels. The scale allows us to rank the severity as critical, high, moderate or low.

This is our assessment and you should evaluate its applicability to your own IT environment.

Description

Bamboo did not check that the name of a branch in a Mercurial repository contained argument parameters. An attacker who has permission to do one or more of the following:

• create a repository in Bamboo
• edit an existing plan in Bamboo that has a non-linked Mercurial repository
• create or edit a plan in Bamboo when there is at least one linked Mercurial repository that the attacker has permission to use
• commit to a Mercurial repository used by a Bamboo plan which has branch detection enabled

can execute code of their choice on systems that run a vulnerable version of Bamboo Server.

Versions of Bamboo starting with 2.7.0 before 6.1.6 (the fixed version for 6.1.x) and from 6.2.0 before 6.2.5 (the fixed version for 6.2.x) are affected by this vulnerability. This issue can be tracked here:  https://jira.atlassian.com/browse/BAM-18843

Acknowledgements

Atlassian would like to credit Zhang Tianqi @ Tophant for reporting this issue to us.

Mitigation

Disable the "Atlassian Bamboo Mercurial Repository Plugin" via the Addons menu in the Administration section.

Fix

We have taken the following steps to address these issues:

1. Released Bamboo version 6.2.5 that contains a fix for these issues and can be downloaded from https://www.atlassian.com/software/bamboo/download.
2. Released Bamboo version 6.1.6 that contains a fix for these issues and can be downloaded from https://www.atlassian.com/software/bamboo/download-archives.

What You Need to Do

Atlassian recommends that you upgrade to the latest version. For a full description of the latest version of Bamboo, see the release notes. You can download the latest version of Bamboo from the download centre.

Upgrade Bamboo to version 6.2.5 or higher.

If you are running Bamboo 6.1.x and cannot upgrade to 6.2.5 then upgrade to version 6.1.6.

Support

If you did not receive an email for this advisory and you wish to receive such emails in the future go to https://my.atlassian.com/email and subscribe to Alerts emails.

If you have questions or concerns regarding this advisory, please raise a support request at https://support.atlassian.com/.

References