title: matrix-appservice-irc events can be crafted to leak parts of targeted messages from other bridged rooms
description: matrix-appservice-irc is a Node.js IRC bridge for Matrix. Prior to version 1.0.1, it was possible to craft an event such that it would leak part of a targeted message event from another bridged room. This required knowing an event ID to target. Version 1.0.1n fixes this issue. As a workaround, set the `matrixHandler.eventCacheSize` config value to `0`. This workaround may impact performance.
problem types: CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
affected:
{
vendor: matrix-org
product: matrix-appservice-irc
versions:
version: < 1.0.1, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 3.5
baseSeverity: LOW
confidentialityImpact: LOW
integrityImpact: NONE
privilegesRequired: LOW
scope: CHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N
version: 3.1
]