VulnerabilityDeferred

CVE-2025-24900

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.

HIGH 8.6EPSS 0.40%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS: 0.40% probability · 34th percentile
CISA KEV: Not listed
Weakness: CWE-352
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.