Most recent entries from all

cnvd-2025-30343

2026-10-08T23:02:47.564017+00:00

cnvd-2025-30343

EUVD-2026-262344

2026-10-08T23:02:47.564055+00:00

EUVD-2026-262344

fkie_cve-2025-66305

2026-10-08T23:02:47.564070+00:00

Grav is a file-based Web platform. Prior to 1.8.0-beta.27, a Denial of Service (DoS) vulnerability was identified in the "Languages" submenu of the Grav admin configuration panel (/admin/config/system). Specifically, the Supported parameter fails to properly validate user input. If a malformed value is inserted—such as a single forward slash (/) or an XSS test string—it causes a fatal regular expression parsing error on the server. This leads to application-wide failure due to the use of the preg_match() function with an improperly constructed regular expression, resulting in an error. Once triggered, the site becomes completely unavailable to all users. This vulnerability is fixed in 1.8.0-beta.27.

GHSA-m8vh-v6r6-w7p6 — Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter

2026-10-08T23:02:47.564107+00:00

Affected: Packagist: getgrav/grav

**Endpoint**: `admin/config/system` **Submenu**: `Languages` **Parameter**: `Supported` **Application**: Grav v 1.7.48

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## Summary

A Denial of Service (DoS) vulnerability was identified in the **"Languages"** submenu of the Grav **admin configuration panel** (`/admin/config/system`). Specifically, the `Supported` parameter fails to properly validate user input. If a malformed value is inserted—such as a single forward slash (`/`) or an XSS test string—it causes a fatal regular expression parsing error on the server.

This leads to application-wide failure due to the use of the `preg_match()` function with an **improperly constructed regular expression**, resulting in the following error:

`preg_match(): Unknown modifier 'o' File: /system/src/Grav/Common/Language/Language.php line 244`

Once triggered, the site becomes completely unavailable to all users.

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## Details

- **Vulnerable Endpoint**: `POST /admin/config/system` - **Submenu**: `Languages` - **Parameter**: `Supported`

The application dynamically constructs a regular expression using the contents of the `Supported` field without escaping the input using `preg_quote()` or proper validation. This allows attackers to inject invalid syntax into the regex engine, crashing the application during language resolution.

**Stack trace excerpt**:

`Whoops \ Exception \ ErrorException (E_WARNING) preg_match(): Unknown modifier 'o' /system/src/Grav/Common/Language/Language.php244`

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## Proof…