8.6
HIGH
CVE-2025-24900
Concorde Misskey CSRF Bypass
Description

Concorde, formerly know as Nexkey, is a fork of the federated microblogging platform Misskey. Due to a lack of CSRF countermeasures and improper settings of cookies for MediaProxy authentication, there is a vulnerability that allows MediaProxy authentication to be bypassed. In versions prior to 12.25Q1.1, the authentication cookie does not have the SameSite attribute. This allows an attacker to bypass MediaProxy authentication and load any image without restrictions under certain circumstances. In versions prior to 12.24Q2.3, this cookie was also used to authenticate the job queue management page (bull-board), so bull-board authentication is also bypassed. This may enable attacks that have a significant impact on availability and integrity. The affected versions are too old to be covered by this advisory, but the maintainers of Concorde strongly recommend not using older versions. Version 12.25Q1.1 contains a patch. There is no effective workaround other than updating.

INFO

Published Date :

Feb. 11, 2025, 4:15 p.m.

Last Modified :

Feb. 11, 2025, 4:15 p.m.

Remotely Exploitable :

Yes !

Impact Score :

4.0

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2025-24900 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 Nexryai nexkey
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-2025-24900.

URL Resource
https://github.com/nexryai/concorde/commit/2309b4a292828ddba4d57cf0e914bc433095871d
https://github.com/nexryai/concorde/commit/f3f54bde6a37ad310f83ae46de54a286c4b74059
https://github.com/nexryai/concorde/security/advisories/GHSA-5hgq-9vw8-7v87

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-2025-24900 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-24900 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]

    Feb. 11, 2025

    Action Type Old Value New Value
    Added Description Concorde, formerly know as Nexkey, is a fork of the federated microblogging platform Misskey. Due to a lack of CSRF countermeasures and improper settings of cookies for MediaProxy authentication, there is a vulnerability that allows MediaProxy authentication to be bypassed. In versions prior to 12.25Q1.1, the authentication cookie does not have the SameSite attribute. This allows an attacker to bypass MediaProxy authentication and load any image without restrictions under certain circumstances. In versions prior to 12.24Q2.3, this cookie was also used to authenticate the job queue management page (bull-board), so bull-board authentication is also bypassed. This may enable attacks that have a significant impact on availability and integrity. The affected versions are too old to be covered by this advisory, but the maintainers of Concorde strongly recommend not using older versions. Version 12.25Q1.1 contains a patch. There is no effective workaround other than updating.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
    Added CWE CWE-352
    Added Reference https://github.com/nexryai/concorde/commit/2309b4a292828ddba4d57cf0e914bc433095871d
    Added Reference https://github.com/nexryai/concorde/commit/f3f54bde6a37ad310f83ae46de54a286c4b74059
    Added Reference https://github.com/nexryai/concorde/security/advisories/GHSA-5hgq-9vw8-7v87
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.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-24900 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-2025-24900 weaknesses.

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability