Sonatype Nexus Repository 3 Security Advisory
Date: July 29th, 2020
Affected Versions: All previous Nexus Repository 3 OSS/Pro versions up to and including 3.25.0
Fixed in Version: Nexus Repository OSS/Pro version 3.25.1
Risk: Medium - 6.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)
Summary:
An XSS vulnerability (CVE-2020-15870) has been discovered in Nexus Repository 3.
A specially crafted request could embed Javascript into content that would later be seen by another user. We have fixed the issue so that HTML and Javascript from the untrusted source will be properly encoded to not be executable. 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.
An external researcher identified this vulnerability and has been verified by our security team. We are not aware of any active exploits taking advantage of this issue. However, we strongly encourage all users of Nexus Repository Manager 3 to immediately take the steps outlined in this advisory.
We are highly recommending all instances of Nexus Repository be upgraded to version 3.25.1 or later.
For detailed information on the upgrade, please see:
https://support.sonatype.com/hc/en-us/articles/115000350007
Credit:
Sonatype thanks nike.zheng@dbappsecurity.com.cn from Dbappsecurity Co., Ltd for responsibly reporting the identified issue and working with us as we addressed it.
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 could craft a URL and send it to a Nexus Repository to view. Once viewed, custom Javascript designed by the attacker would run on the victim's computer with the victim's authentication/authorization.
Q: What preconditions must be met in order to be vulnerable?
A: An attacker must have network access to the Nexus Repository instance in order to view protected content such as configuration files. Therefore, internet-accessible instances imply available access by a very large audience versus the more limited audience associated with non-internet-accessible instances.
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 best to protect our user community, we are limiting the information released to that absolutely required to assess the impact and effect of 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 over 150,000 active server installations, notifying the user base will invariably lead to broad dissemination. We are taking a concerted and proactive approach in our outreach activities and in an effort to achieve the most rapid remediation possible.