plone.namedfile vulnerable to Stored Cross Site Scripting with SVG images

Impact

There is a stored cross site scripting vulnerability for SVG images. A security hotfix from 2021 already partially fixed this, by making sure SVG images are always downloaded instead of shown inline. But the same problem still exists for scales of SVG images.

Note that an image tag with an SVG image as source is not vulnerable, even when the SVG image contains malicious code. To exploit the vulnerability, an attacker would first need to upload an image, and then trick a user into following a specially crafted link.

All versions of plone.namedfile are impacted.

Patches

Patches will be released in various plone.namedfile releases:

• 5.6.1 (for Plone 5.2)
• 6.0.3 (for Plone 6.0.0-6.0.4)
• 6.1.3 (for Plone 6.0.5-6.0.6)
• 6.2.1 (for Plone 6.0.7)

Workarounds

There is no workaround.