CVE-2025-66305
published 2025-12-01CVE-2025-66305: 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…
PriorityP423medium4.9CVSS 3.1
AVNACLPRHUINSUCNINAH
EPSS
0.34%
25.5th percentile
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.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| getgrav | grav | < 1.8.0-beta.27 | 1.8.0-beta.27 |
| getgrav | grav | — | — |
| getgrav | grav | >= 0 < 1.8.0-beta.27 | 1.8.0-beta.27 |
| getgrav | grav | >= 1.7.48 < 1.8.0 | 1.8.0 |
CVSS provenance
nvdv3.14.9MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
nvdv4.06.9MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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GHSA
Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
ghsa·2025-12-02
CVE-2025-66305 [HIGH] CWE-248 Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
**Endpoint**: `admin/config/system`
**Submenu**: `Languages`
**Parameter**: `Supported`
**Application**: Grav v 1.7.48
---
## 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
OSV
Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
osv·2025-12-02
CVE-2025-66305 [HIGH] Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter
**Endpoint**: `admin/config/system`
**Submenu**: `Languages`
**Parameter**: `Supported`
**Application**: Grav v 1.7.48
---
## 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
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-12-01
Published