9.3
CRITICAL CVSS 4.0
CVE-2026-24471
Improper Validation in Conduit-derived homeservers resulting in Unintended Proxy or Intermediary ('Confused Deputy')
Description

continuwuity is a Matrix homeserver written in Rust. This vulnerability allows an attacker with a malicious remote server to cause the local server to sign an arbitrary event upon user interaction. Upon a user account leaving a room (rejecting an invite), joining a room or knocking on a room, the victim server may ask a remote server for assistance. If the victim asks the attacker server for assistance the attacker is able to provide an arbitrary event, which the victim will sign and return to the attacker. For the /leave endpoint, this works for any event with a supported room version, where the origin and origin_server_ts is set by the victim. For the /join endpoint, an additionally victim-set content field in the format of a join membership is needed. For the /knock endpoint, an additional victim-set content field in the format of a knock membership and a room version not between 1 and 6 is needed. This was exploited as a part of a larger chain against the continuwuity.org homeserver. This vulnerability affects all Conduit-derived servers. This vulnerability is fixed in Continuwuity 0.5.1, Conduit 0.10.11, Grapevine 0aae932b, and Tuwunel 1.4.9.

INFO

Published Date :

Feb. 2, 2026, 11:16 p.m.

Last Modified :

Feb. 2, 2026, 11:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-24471 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.

No affected product recoded yet

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 4.0 CRITICAL [email protected]
Solution
Update Conduit-derived servers to patched versions to prevent arbitrary event signing.
  • Update Continuwuity to 0.5.1 or later.
  • Update Conduit to 0.10.11 or later.
  • Update Grapevine to 0aae932b or later.
  • Update Tuwunel to 1.4.9 or later.
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-2026-24471.

URL Resource
https://forgejo.ellis.link/continuwuation/continuwuity/commit/12aecf809172205436c852a1eaf268c1a2c3a900
https://github.com/continuwuity/continuwuity/security/advisories/GHSA-m5p2-vccg-8c9v
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-24471 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-2026-24471 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-2026-24471 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-24471 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. 02, 2026

    Action Type Old Value New Value
    Added Description continuwuity is a Matrix homeserver written in Rust. This vulnerability allows an attacker with a malicious remote server to cause the local server to sign an arbitrary event upon user interaction. Upon a user account leaving a room (rejecting an invite), joining a room or knocking on a room, the victim server may ask a remote server for assistance. If the victim asks the attacker server for assistance the attacker is able to provide an arbitrary event, which the victim will sign and return to the attacker. For the /leave endpoint, this works for any event with a supported room version, where the origin and origin_server_ts is set by the victim. For the /join endpoint, an additionally victim-set content field in the format of a join membership is needed. For the /knock endpoint, an additional victim-set content field in the format of a knock membership and a room version not between 1 and 6 is needed. This was exploited as a part of a larger chain against the continuwuity.org homeserver. This vulnerability affects all Conduit-derived servers. This vulnerability is fixed in Continuwuity 0.5.1, Conduit 0.10.11, Grapevine 0aae932b, and Tuwunel 1.4.9.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:H/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
    Added CWE CWE-441
    Added Reference https://forgejo.ellis.link/continuwuation/continuwuity/commit/12aecf809172205436c852a1eaf268c1a2c3a900
    Added Reference https://github.com/continuwuity/continuwuity/security/advisories/GHSA-m5p2-vccg-8c9v
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: 9.3
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability