Description
An issue was discovered in Barrier before 2.4.0. An attacker can enter an active session state with the barriers component (aka the server-side implementation of Barrier) simply by supplying a client label that identifies a valid client configuration. This label is "Unnamed" by default but could instead be guessed from hostnames or other publicly available information. In the active session state, an attacker can capture input device events from the server, and also modify the clipboard content on the server.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 15 SP3 | barrier | 2.4.0-bp153.2.3.1 | openSUSE-SU-2021:1595-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | barrier | 2.4.0-1.1 | openSUSE-SU-2024:11633-1 |
| openSUSE Leap 15.3 | barrier | 2.4.0-bp153.2.3.1 | openSUSE-SU-2021:1595-1 |
| openSUSE Leap 15.2 | barrier | 2.4.0-lp152.3.6.1 | openSUSE-SU-2021:1498-1 |
Advisories 3
- openSUSE-SU-2021:1595-1 Security update for barrier SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11633-1 barrier-2.4.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:1498-1 Security update for barrier SUSE / openSUSE Security Updates · Feb 4, 2026
References
- [oss-security] 20211102 Barrier "software KVM switch" multiple remote security issues mailing-list
- https://github.com/debauchee/barrier/releases/tag/v2.4.0
- https://github.com/debauchee/barrier/commit/b5adc93e2bd74cb094f91ff595c07f321a489f3e
- https://github.com/debauchee/barrier/commit/229abab99f39f11624e5651f819e7f1f8eddedcc