CVE-2021-34426: Arbitrary command execution in Keybase Client for Windows

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-12-14 · updated 2026-06-17

Description

A vulnerability was discovered in the Keybase Client for Windows before version 5.6.0 when a user executed the "keybase git lfs-config" command on the command-line. In versions prior to 5.6.0, a malicious actor with write access to a user\'s Git repository could leverage this vulnerability to potentially execute arbitrary Windows commands on a user\'s local system.

Affected products

Zoom Video Communications Inc Keybase Client for Windows: before 5.6.0 — fixed in 5.6.0

How to fix

Upgrade to a fixed version: Zoom Video Communications Inc Keybase Client for Windows 5.6.0. Check the vendor advisory for mitigations.

References

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