CVE-2021-47955 CouchCMS 2.2.1 Cross-Site Scripting via SVG File Upload
Authenticated attackers can execute arbitrary JavaScript in users' browsers by uploading malicious SVG files to CouchCMS.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2021-47955?
CVE-2021-47955 is a medium-severity cross-site scripting vulnerability in CouchCMS, published on 16 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
CouchCMS 2.2.1 contains a cross-site scripting vulnerability that allows authenticated attackers to execute arbitrary JavaScript by uploading malicious SVG files through the file upload functionality. Attackers can upload SVG files containing embedded script tags to the browse.php endpoint, which are then executed in users' browsers when the files are accessed or previewed.
Weakness: CWE-79
Which versions are affected by CVE-2021-47955?
How do I fix CVE-2021-47955?
No fix has been published for CVE-2021-47955 yet. Limit exposure of the affected software until one is available.
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-2021-47955 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47955 exists.
Sources
Also known as GHSA-7q3g-gccm-822q.