CVE-2022-39203 - CVE House
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Status published High CVE-2022-39203

Parsing issue in matrix-org/node-irc leading to room takeovers

Vulnerability Description

matrix-appservice-irc is an open source Node.js IRC bridge for Matrix. Attackers can specify a specific string of characters, which would confuse the bridge into combining an attacker-owned channel and an existing channel, allowing them to grant themselves permissions in the channel. The vulnerability has been patched in matrix-appservice-irc 0.35.0. As a workaround operators may disable dynamic channel joining via `dynamicChannels.enabled` to prevent users from joining new channels, which prevents any new channels being bridged outside of what is already bridged, and what is specified in the config.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

matrix-appservice-irc
Vulnerable Versions:
< 0.35.0

Timeline

Official Publish: September 13th, 2022
Last Modified: April 23rd, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses (CWE)

CWE-269

MITRE ATT&CK TTPs

T1078 Valid Accounts
Persistence
T1098 Account Manipulation
Privilege Escalation
T1548 Abuse Elevation Control Mechanism
Privilege Escalation
T1222 File and Directory Permissions Modification
Defense Evasion
T1134 Access Token Manipulation
Defense Evasion