Nextcloud Server up to 13.0.4 Autocomplete Stored cross site scripting

Summaryinfo

A vulnerability labeled as problematic has been found in Nextcloud Server up to 13.0.4. This vulnerability affects unknown code of the component Autocomplete Handler. Executing a manipulation can lead to cross site scripting (Stored). This vulnerability appears as CVE-2018-3780. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Nextcloud Server up to 13.0.4 (Cloud Software) and classified as problematic. This vulnerability affects an unknown part of the component Autocomplete Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability (Stored). The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. CVE summarizes:

A missing sanitization of search results for an autocomplete field in NextCloud Server <13.0.5 could lead to a stored XSS requiring user-interaction. The missing sanitization only affected user names, hence malicious search results could only be crafted by authenticated users.

The bug was discovered 08/10/2018. The weakness was presented 08/13/2018 (Website). The advisory is available at nextcloud.com. This vulnerability was named CVE-2018-3780 since 12/27/2017. The attack can be initiated remotely. A single authentication is necessary for exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

The vulnerability was handled as a non-public zero-day exploit for at least 3 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 112141 (openSUSE Security Update : nextcloud (openSUSE-2018-936)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 171539 (OpenSUSE Security Update for nextcloud (openSUSE-SU-2018:2521-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (112141). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Cloud Software

Name

• Nextcloud Server

Version

• 13.0.0
• 13.0.1
• 13.0.2
• 13.0.3
• 13.0.4

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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