CVE-2026-54555

Name of the Vulnerable Software and Affected Versions rtk versions prior to 0.42.2

Description A flaw in the permission splitter logic fails to conservatively split or reject certain Bash shell constructs that create command-execution boundaries or nested execution. This improper input validation and parsing of shell syntax allows a permitted prefix, such as 'git', to mask an additional command. Consequently, the rtk rewrite function returns exit code 0, leading the Claude hook to emit a permissionDecision of "allow". This enables the hidden command to execute without the user confirmation or denial intended by the permission rules, potentially leading to unauthorized command execution under the user's context.

Recommendations Update to version 0.42.2.