CVE-2023-40013 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in external-svg-loader
Attackers can execute arbitrary JavaScript via malicious SVGs due to insufficient sanitization in external-svg-loader, affecting websites allowing user-provided SVGs.
- 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-2023-40013?
CVE-2023-40013 is a high-severity cross-site scripting vulnerability in shubhamjain svg-loader, published on 14 Aug 2023. 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
SVG Loader is a javascript library that fetches SVGs using XMLHttpRequests and injects the SVG code in the tag's place. According to the docs, svg-loader will strip all JS code before injecting the SVG file for security reasons but the input sanitization logic is not sufficient and can be trivially bypassed. This allows an attacker to craft a malicious SVG which can result in Cross-site Scripting (XSS). When trying to sanitize the svg the lib removes event attributes such as `onmouseover`, `onclick` but the list of events is not exhaustive. Any website which uses external-svg-loader and allows its users to provide svg src, upload svg files would be susceptible to stored XSS attack. This issue has been addressed in commit `d3562fc08` which is included in releases from 1.6.9. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Weakness: CWE-79
Which versions are affected by CVE-2023-40013?
2 open source packages ship an affected version, including external-svg-loader. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
external-svg-loader npm | All versions | 1.6.9 |
external-svg-loader npm | All versions | 1.6.9 |
Products include Shubhamjain Svg Loader.
How do I fix CVE-2023-40013?
Upgrade external-svg-loader to 1.6.9 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-2023-40013 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-40013 exists.
Sources
Also known as GHSA-xc2r-jf2x-gjr8.