CVE-2024-21535 Cross site scripting in markdown-to-jsx
An attacker can execute arbitrary code by injecting a malicious iframe into markdown content processed by the markdown-to-jsx library.
- 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
- Available
What is CVE-2024-21535?
CVE-2024-21535 is a medium-severity cross-site scripting vulnerability in markdown-to-jsx, published on 15 Oct 2024. 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
Versions of the package markdown-to-jsx before 7.4.0 are vulnerable to Cross-site Scripting (XSS) via the src property due to improper input sanitization. An attacker can execute arbitrary code by injecting a malicious iframe element in the markdown.
Weakness: CWE-79
Which versions are affected by CVE-2024-21535?
2 open source packages ship an affected version, including markdown-to-jsx. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
markdown-to-jsx npm | All versions | 7.4.0 |
markdown-to-jsx npm | All versions | 7.4.0 |
Products include Quantizor Markdown-to-Jsx.
How do I fix CVE-2024-21535?
Upgrade markdown-to-jsx to 7.4.0 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-2024-21535 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-21535 exists.
Sources
Also known as DEBIAN-CVE-2024-21535, GHSA-4wx3-54gh-9fr9, UBUNTU-CVE-2024-21535.