5.0
MEDIUM CVSS 3.1
CVE-2025-66407
Weblate has Server-Side Request Forgery vulnerability
Description

Weblate is a web based localization tool. The Create Component functionality in Weblate allows authorized users to add new translation components by specifying both a version control system and a source code repository URL to pull from. However, prior to version 5.15, the repository URL field is not validated or sanitized, allowing an attacker to supply arbitrary protocols, hostnames, and IP addresses, including localhost, internal network addresses, and local filenames. When the Mercurial version control system is selected, Weblate exposes the full server-side HTTP response for the provided URL. This effectively creates a server-side request forgery (SSRF) primitive that can probe internal services and return their contents. In addition to accessing internal HTTP endpoints, the behavior also enables local file enumeration by attempting file:// requests. While file contents may not always be returned, the application’s error messages clearly differentiate between files that exist and files that do not, revealing information about the server’s filesystem layout. In cloud environments, this behavior is particularly dangerous, as internal-only endpoints such as cloud metadata services may be accessible, potentially leading to credential disclosure and full environment compromise. This has been addressed in the Weblate 5.15 release. As a workaround, remove Mercurial from `VCS_BACKENDS`; the Git backend is not affected. The Git backend was already configured to block the file protocol and does not expose the HTTP response content in the error message.

INFO

Published Date :

Dec. 16, 2025, 12:16 a.m.

Last Modified :

Oct. 7, 2026, 7:10 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2025-66407 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Weblate weblate
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 3.1 MEDIUM [email protected]
Solution
Update Weblate to version 5.15 or later to fix SSRF and file enumeration vulnerabilities.
  • Update Weblate to version 5.15 or later.
  • Remove Mercurial from VCS_BACKENDS as a workaround.
  • Configure Git backend to block file protocol.
  • Ensure HTTP response content is not exposed.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-66407.

URL Resource
https://github.com/WeblateOrg/weblate/pull/17102 Issue Tracking Patch
https://github.com/WeblateOrg/weblate/pull/17103 Issue Tracking Patch
https://github.com/WeblateOrg/weblate/security/advisories/GHSA-hfpv-mc5v-p9mm Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-66407 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-66407 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-66407 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Translated by [email protected]

    Oct. 07, 2026

    Action Type Old Value New Value
    Added Translation Title: weblate de WeblateOrg, Description: Weblate es una herramienta de localización basada en web. La funcionalidad 'Crear Componente' en Weblate permite a los usuarios autorizados añadir nuevos componentes de traducción especificando tanto un sistema de control de versiones como una URL de repositorio de código fuente de la que extraer. Sin embargo, antes de la versión 5.15, el campo de la URL del repositorio no está validado ni saneado, lo que permite a un atacante suministrar protocolos, nombres de host y direcciones IP arbitrarios, incluyendo localhost, direcciones de red internas y nombres de archivo locales. Cuando se selecciona el sistema de control de versiones Mercurial, Weblate expone la respuesta HTTP completa del lado del servidor para la URL proporcionada. Esto crea efectivamente una primitiva de falsificación de petición del lado del servidor (SSRF) que puede sondear servicios internos y devolver sus contenidos. Además de acceder a puntos finales HTTP internos, el comportamiento también permite la enumeración de archivos locales al intentar peticiones file: //. Aunque el contenido de los archivos no siempre se devuelva, los mensajes de error de la aplicación diferencian claramente entre los archivos que existen y los que no, revelando información sobre la estructura del sistema de archivos del servidor. En entornos de nube, este comportamiento es particularmente peligroso, ya que los puntos finales solo internos, como los servicios de metadatos de la nube, pueden ser accesibles, lo que podría llevar a la divulgación de credenciales y al compromiso total del entorno. Esto ha sido abordado en la versión 5.15 de Weblate. Como solución alternativa, elimine Mercurial de 'VCS_BACKENDS'; el backend de Git no está afectado. El backend de Git ya estaba configurado para bloquear el protocolo de archivo y no expone el contenido de la respuesta HTTP en el mensaje de error.
  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'WeblateOrg', 'product': 'weblate', 'versions': [{'status': 'affected', 'version': '< 5.15'}]}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2025-66407', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2025-12-16T19:07:51.759310Z'}
  • Initial Analysis by [email protected]

    Jan. 12, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
    Added CWE CWE-918
    Added CPE Configuration OR *cpe:2.3:a:weblate:weblate:*:*:*:*:*:*:*:* versions up to (excluding) 5.15
    Added Reference Type GitHub, Inc.: https://github.com/WeblateOrg/weblate/pull/17102 Types: Issue Tracking, Patch
    Added Reference Type GitHub, Inc.: https://github.com/WeblateOrg/weblate/pull/17103 Types: Issue Tracking, Patch
    Added Reference Type GitHub, Inc.: https://github.com/WeblateOrg/weblate/security/advisories/GHSA-hfpv-mc5v-p9mm Types: Vendor Advisory
  • New CVE Received by [email protected]

    Dec. 16, 2025

    Action Type Old Value New Value
    Added Description Weblate is a web based localization tool. The Create Component functionality in Weblate allows authorized users to add new translation components by specifying both a version control system and a source code repository URL to pull from. However, prior to version 5.15, the repository URL field is not validated or sanitized, allowing an attacker to supply arbitrary protocols, hostnames, and IP addresses, including localhost, internal network addresses, and local filenames. When the Mercurial version control system is selected, Weblate exposes the full server-side HTTP response for the provided URL. This effectively creates a server-side request forgery (SSRF) primitive that can probe internal services and return their contents. In addition to accessing internal HTTP endpoints, the behavior also enables local file enumeration by attempting file:// requests. While file contents may not always be returned, the application’s error messages clearly differentiate between files that exist and files that do not, revealing information about the server’s filesystem layout. In cloud environments, this behavior is particularly dangerous, as internal-only endpoints such as cloud metadata services may be accessible, potentially leading to credential disclosure and full environment compromise. This has been addressed in the Weblate 5.15 release. As a workaround, remove Mercurial from `VCS_BACKENDS`; the Git backend is not affected. The Git backend was already configured to block the file protocol and does not expose the HTTP response content in the error message.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
    Added CWE CWE-352
    Added Reference https://github.com/WeblateOrg/weblate/pull/17102
    Added Reference https://github.com/WeblateOrg/weblate/pull/17103
    Added Reference https://github.com/WeblateOrg/weblate/security/advisories/GHSA-hfpv-mc5v-p9mm
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.