CVE-2025-68667Conduit is a chat server powered by Matrix.

Conduit is a chat server powered by Matrix. A vulnerability that affects a number of Conduit-derived homeservers allows a remote, unauthenticated attacker to force the target server to cryptographically sign arbitrary membership events. Affected products include Conduit prior to version 0.10.10, continuwuity prior to version 0.5.0, Grapevine prior to commit `9a50c244`, and tuwunel prior to version 1.4.8. The flaw exists because the server fails to validate the origin of a signing request, provided the event's state_key is a valid user ID belonging to the target server. Attackers can forge "leave" events for any user on the target server. This forcibly removes users (including admins and bots) from rooms. This allows denial of service and/or the removal of technical protections for a room (including policy servers, if all users on the policy server are removed). Attackers can forge "invite" events from a victim user to themselves, provided they have an account on a server where there is an account that has the power level to send invites. This allows the attacker to join private or invite-only rooms accessible by the victim, exposing confidential conversation history and room state. Attackers can forge "ban" events from a victim user to any user below the victim user's power level, provided the victim has the power level to issue bans AND the target of the ban resides on the same server as the victim. This allows the attacker to ban anyone in a room who is on the same server as the vulnerable one, however cannot exploit this to ban users on other servers or the victim themself. Conduit fixes the issue in version 0.10.10. continuwuity fixes the issue in commits `7fa4fa98` and `b2bead67`, released in 0.5.0. tuwunel fixes the issue in commit `dc9314de1f8a6e040c5aa331fe52efbe62e6a2c3`, released in 1.4.8. Grapevine fixes the issue in commit `9a50c2448abba6e2b7d79c64243bb438b351616c`. As a workaround, block access to the `PUT /_matrix/federation/v2/invite/{roomId}/{eventId}` endpoint using your reverse proxy.

CVSS

9.9 CRITICAL (v4.0, NVD)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:L/SA:L/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

Weakness (CWE)

CWE-20, CWE-441

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

Not given

NVD analysis

Deferred

Record last updated

Jun 17, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.