CVE-2025-68467 Dark Reader gives users the ability to request style sheets from local web servers
A malicious website can force the Dark Reader extension to request style sheets from local servers, potentially exposing local resources.
- 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-2025-68467?
CVE-2025-68467 is a low-severity server-side request forgery vulnerability in darkreader, published on 4 Mar 2026. 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
Dark Reader is an accessibility browser extension that makes web pages colors dark. The dynamic dark mode feature of the extension works by analyzing the colors of web pages found in CSS style sheet files. In order to analyze cross-origin style sheets (stored on websites different from the original web page), Dark Reader requests such files via a background worker, ensuring the request is performed with no credentials and that the content type of the response is a CSS file. Prior to Dark Reader 4.9.117, this style content was assigned to an HTML Style Element in order to parse and loop through style declarations, and also stored in page's Session Storage for performance gains. This could allow a website author to request a style sheet from a locally running web server, for example by having a link pointing to `http[:]//localhost[:]8080/style[.]css`. The brute force of the host name, port and file name would be unlikely due to performance impact, that would cause the browser tab to hang shortly, but it could be possible to request a style sheet if the full URL was known in advance. As per December 18, 2025 there is no known exploit of the issue. The problem has been fixed in version 4.9.117 on December 3, 2025. The style sheets are now parsed using modern Constructed Style Sheets API and the contents of cross-origin style sheets is no longer stored in page's Session Storage. Version 4.9.118 (December 8, 2025) restricts cross-origin requests to localhost aliases, IP addresses, hosts with ports and non-HTTPS resources. The absolute majority of users have received an update 4.1.117 or 4.9.118 automatically within a week. However users must ensure their automatic updates are not blocked and they are using the latest version of the extension by going to chrome://extensions or about:addons pages in browser settings. Users utilizing manual builds must upgrade to version 4.9.118 and above. Developers using `darkreader` NPM package for their own websites are likely not affected, but must ensure the function passed to `setFetchMethod()` for performing cross-origin requests works within the intended scope. Developers using custom forks of earlier versions of Dark Reader to build other extensions or integrating into their apps or browsers must ensure they perform cross-origin requests safely and the responses are not accessible outside of the app or extension.
Which versions are affected by CVE-2025-68467?
2 open source packages ship an affected version, including darkreader. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
darkreader npm | All versions | 4.9.117 |
darkreader npm | All versions | 4.9.117 |
Products include Darkreader Darkreader.
How do I fix CVE-2025-68467?
Upgrade darkreader to 4.9.117 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2025-68467 being exploited?
There is no known exploitation of CVE-2025-68467 in the wild and no public exploit code.
Sources
Also known as GHSA-x369-mcw8-8rvj.