CVE-2022-29166

Improper handling of multiline messages in matrix-appservice-irc

8.0 HighFix available

matrix-appservice-irc is a Node.js IRC bridge for Matrix. The vulnerability in node-irc allows an attacker to manipulate a Matrix user into executing IRC commands by having them reply to a maliciously crafted message. The vulnerability has been patched in matrix-appservice-irc 0.33.2. Refrain from replying to messages from untrusted participants in IRC-bridged Matrix rooms. There are no known workarounds for this issue.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: Required

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

1.00%Up 0.1 points since May 6, 2022

What each source reports

CVE List Score used 8.0

Improper handling of multiline messages in matrix-appservice-irc

Record: CVE-2022-29166
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-74
Updated: 2026-11-02

EUVDEUVD-2022-2126 8.0

Record: EUVD-2022-2126
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Updated: 2026-11-02

GitHub AdvisoriesGHSA-37hr-348p-rmf4 8.0

Improper handling of multiline messages in node-irc affects matrix-appservice-irc

matrix-appservice-irc provides an IRC bridge for Matrix. The vulnerability in node-irc allows an attacker to manipulate a Matrix user into executing IRC commands by having them reply to a maliciously crafted message. The vulnerability has been patched in matrix-appservice-irc 0.33.2. In terms of a workaround, users should refrain from replying to messages from untrusted participants in IRC-bridged Matrix rooms.

Record: GHSA-37hr-348p-rmf4
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-74
Updated: 2026-11-02

NVD 8.0

Record: CVE-2022-29166
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
CVSS 3.1: 8.8 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS 2.0: 6.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness: CWE-74
Updated: 2026-11-02

OSV 8.0

Improper handling of multiline messages in matrix-appservice-irc

Record: CVE-2022-29166
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-74
Updated: 2026-11-02

OSVGHSA-37hr-348p-rmf4 8.0

Improper handling of multiline messages in node-irc affects matrix-appservice-irc

Record: GHSA-37hr-348p-rmf4
CVSS 3.1: 8.0 HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-74
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`matrix-appservice-irc` npm	through 0.33.1	0.33.2
`matrix-appservice-irc` npm	before 0.33.2	0.33.2

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2022-29166 is a high vulnerability (CVSS 8.0) in Matrix Irc Bridge, published May 5, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.00%, the 63rd percentile. Fixed in matrix-appservice-irc 0.33.2.