CVE-2026-105429 NetBird client SSH config Match line injection via peer FQDN or hostname allows local command execution
A malicious peer can inject SSH config directives via hostname to execute arbitrary commands on NetBird client hosts.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-105429?
CVE-2026-105429 is a high-severity command injection vulnerability in NetBird, published on 14 Oct 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Improper neutralization of special elements in the NetBird client SSH configuration manager (client/ssh/config/manager.go) in NetBird versions 0.60.0 through 0.74.6 allows a malicious or compromised peer to execute arbitrary commands on other NetBird client hosts. The client writes a system-wide OpenSSH drop-in file (/etc/ssh/ssh_config.d/99-netbird.conf, or the equivalent under %PROGRAMDATA%\ssh\ssh_config.d on Windows) that embeds each peer FQDN or hostname inside a double-quoted Match host directive without escaping. A peer name containing a double quote breaks out of the quoted context and injects arbitrary SSH configuration directives, including exec commands, which run locally as any user on the host the next time that user runs ssh. Desktop clients on Linux, macOS, Windows and FreeBSD are affected; the Android and iOS apps are not. The issue is fixed in version 0.74.7, which accepts a peer FQDN or hostname only if it is a valid DNS name.
Which versions are affected by CVE-2026-105429?
How do I fix CVE-2026-105429?
No fix has been published for CVE-2026-105429 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-105429 being exploited?
There is no known exploitation of CVE-2026-105429 in the wild and no public exploit code.
Sources
Also known as GHSA-2rq5-4vw4-m3vg, GHSA-xmg2-v32j-x2hf.