CVE-2023-33182 Nextcloud Contacts photos only sanitized if mime type is all lower case

None 0.0 Published 30 May 2023 Updated 10 Jan 2025

Attackers could potentially execute scripts via unsanitized SVGs in Nextcloud Contacts if mime type casing is manipulated, though exploitation is currently deemed unlikely.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2023-33182?

CVE-2023-33182 is a cross-site scripting vulnerability in nextcloud security-advisories, published on 30 May 2023. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Contacts app for Nextcloud easily syncs contacts from various devices with your Nextcloud and allows editing. The unsanitized SVG is converted to a JavaScript blob (in memory data) that the Avatar can't render. Due to this constellation the missing sanitization does not seem to be exploitable. It is recommended that the Contacts app is upgraded to 5.0.3 or 4.2.4

Weakness: CWE-20

Which versions are affected by CVE-2023-33182?

It affects 1 product.

Products include Nextcloud Contacts.

How do I fix CVE-2023-33182?

No fix has been published for CVE-2023-33182 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-2023-33182 being exploited?

There is no known exploitation of CVE-2023-33182 in the wild and no public exploit code.

Sources

Also known as GHSA-hxr6-cx85-gcjx.