CVE-2020-8294 Cross-site scripting in Nextcloud Server
Attackers can execute stored XSS via javascript URLs in markdown, potentially compromising user sessions in Internet Explorer.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2020-8294?
CVE-2020-8294 is a medium-severity cross-site scripting vulnerability in Nextcloud Nextcloud Server, published on 3 Feb 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format.
Weakness: CWE-79
Which versions are affected by CVE-2020-8294?
It affects 1 product.
Products include Nextcloud Nextcloud Server.
How do I fix CVE-2020-8294?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2020-8294 being exploited?
There is no known exploitation of CVE-2020-8294 in the wild and no public exploit code.
Other vulnerabilities in Nextcloud Nextcloud Server
- CVE-2021-32802 Preview generation used third-party library not suited for user-generated content in Nextcloud server
- CVE-2023-26482 Scope of workflow operations is not validated in nextcloud server
- CVE-2018-3775 Auth bypass in Nextcloud Server
- CVE-2023-35172 Nextcloud Server password reset endpoint is not brute force protected
- CVE-2023-32320 Nextcloud Server's brute force protection allows someone to send more requests than intended
Sources
Also known as GHSA-mjfh-rmmm-2mm7.