Sonatype Nexus Security Advisory
Date: March 31, 2020
Affected Versions: All previous Nexus Repository 3.x OSS/Pro versions up to and including 3.21.1
Fixed in Version: Nexus Repository OSS/Pro version 3.21.2
Risk: Critical - 10.0 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)
Summary:
A cross-site scripting (XSS) vulnerability have been discovered in Nexus Repository 3.
An attacker with elevated privileges can create entities with specially crafted properties which, when viewed by another user, can execute arbitrary JavaScript in the context of the Nexus Repository application. We have fixed the issue by ensuring the values are properly encoded. This advisory provides the pertinent information needed to properly address this vulnerability, along with the details on how to reach us if you have any further questions or concerns.
We are not aware of any active exploits taking advantage of this issue. However, we strongly encourage all users of Nexus Repository to immediately take the steps outlined in this advisory.
The identified vulnerability allows arbitrary JavaScript to run in an Nexus Repository user's browser in the context of the application. In regards to XSS, it is common that the injected JavaScript could forge requests on behalf of the user, redirect the user to another site or modify the page content.
Recommendation:
We are highly recommending all affected instances of Nexus Repository 3 be upgraded to 3.21.2 or later.
For detailed information on upgrade, please see:
Upgrading Nexus Repository Manager 3.1.0 and Newer
Credit:
This issue was discovered and reported by Github Security Lab team member pwntester (Alvaro Muñoz).
Support:
If you run into any problems, or have any questions/concerns, please contact us by filing a ticket at https://support.sonatype.com.
Frequently Asked Questions:
Q: What is the risk associated with this vulnerability?
A: An attacker with elevated privileges can create entities with specially crafted properties which when viewed would execute arbitrary JavaScript within the context of the application leading to the compromise of the confidentiality and integrity of data.
Q: What preconditions must be met in order to be vulnerable?
A: An attacker must have elevated privileges and another user must view malicious entities.
Q: Are there implications associated with this advisory itself?
A: Disclosure unfortunately means bad actors may try to take advantage. While we have initially limited the information to the minimum details necessary for users to affect an appropriate fix, this merely slows down a would be attacker. As such, we are advising all organizations utilizing Nexus Repository to immediately assess their individual impact and take appropriate action in response.
Q: Where can I obtain more information associated with the vulnerability?
A: At this time, and in the interest of best protecting our user community, we are limiting the information released to that absolutely required in order to assess impact and affect remediation. Please contact support for more information.
Q: Why is Sonatype making this information available?
A: This is part of a responsible disclosure process. Given Nexus Repository is an open source project with widespread usage, notifying the user base will invariably lead to broad dissemination. We are taking a concerted and proactive approach in our outreach activities and an effort to achieve the most rapid remediation possible.