Quick answers
- Is CVE-2026-75831 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-75831 being exploited in the wild.
- How severe is CVE-2026-75831?
- High severity, with a CVSS score of 7.6, published 18 August 2026.
- Which products and versions are affected?
- Grav 2.0.13 and earlier, including develop branch; getgrav/grav (Packagist) <= 2.0.14, ECOSYSTEM:introduced=0,fixed=2.0.15.
- Is there a fix for CVE-2026-75831?
- Yes. getgrav/grav (Packagist): upgrade to 2.0.15 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-75831 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-75831?
- Check whether you run Grav or getgrav/grav (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- getgrav/grav (Packagist): upgrade to 2.0.15 or later
composer require getgrav/grav:^2.0.15
Technical details
A stored cross-site scripting (XSS) vulnerability exists in Grav's AudioMediaTrait and VideoMediaTrait classes, where the `sourceParsedownElement()` method concatenates media URLs directly into a Parsedown rawHtml element without HTML escaping. The vulnerable code builds `<source src="$location">` by string concatenation, where $location includes the URL fragment unencoded. An attacker can inject markup like `song.mp3#"><svg/onload=alert(1)>` to break out of the src attribute and inject arbitrary HTML/JavaScript. The fragment passes through Excerpts.php which decodes it with htmlspecialchars_decode and urldecode, stripping prior escaping. The built-in tagfilter fails to block `<svg>` and `<img>` tags, allowing event handlers like `onload` to execute. The fix requires escaping $location with htmlspecialchars() before concatenation or using Parsedown's attribute-escaping mechanism instead of rawHtml.
Affected products
- Grav Grav 2.0.13 and earlier, including develop branch
Identifiers
- CVE-2026-75831
- GHSA-6qw9-4vv5-jr97
Timeline
- 2026-09-17: disclosed
- other: CVE-2026-75831 assigned