CVE-2021-35959 Plone has stored XSS in folder contents
Attackers can execute arbitrary scripts in the folder contents view via malicious folder descriptions, affecting Plone CMS users.
- 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-2021-35959?
CVE-2021-35959 is a medium-severity cross-site scripting vulnerability in Plone Plone, published on 30 Jun 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
In Plone 5.0 through 5.2.4, Editors are vulnerable to XSS in the folder contents view, if a Contributor has created a folder with a SCRIPT tag in the description field.
Weakness: CWE-79
Which versions are affected by CVE-2021-35959?
3 open source packages ship an affected version, including plone and Plone. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
plone PyPI | From 5.0 to 5.2.4 | None |
plone PyPI | From 5.0 | 5.2.5 |
Plone PyPI | From 5.0 to 5.2.4 | None |
Products include Plone Plone.
How do I fix CVE-2021-35959?
Upgrade plone to 5.2.5 or later.
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-2021-35959 being exploited?
There is no known exploitation of CVE-2021-35959 in the wild and no public exploit code.
Other vulnerabilities in Plone Plone
Sources
Also known as GHSA-qfhw-fv3g-v836, PYSEC-2021-110.