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 :

Dec. 16, 2025, 2:10 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 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
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
https://github.com/WeblateOrg/weblate/pull/17103
https://github.com/WeblateOrg/weblate/security/advisories/GHSA-hfpv-mc5v-p9mm
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)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-66407 weaknesses.

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.

  • 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.
Vulnerability Scoring Details
Base CVSS Score: 5.0
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact