CVE-2026-54555 | rtk filters and compresses command outputs before they reach… | CVSS 7.8 HIGH

Description

rtk filters and compresses command outputs before they reach your LLM context. Prior to 0.42.2, the permission splitter did not conservatively split or reject several shell constructs that Bash treats as command execution boundaries or nested execution. As a result, a command beginning with an allowed prefix such as git could hide a second command behind one of these constructs. rtk rewrite returned exit code 0, causing the Claude hook to emit permissionDecision: "allow". The rewritten command still contained the hidden command, so it ran without the user confirmation or denial that the permission rules were intended to enforce. This vulnerability is fixed in 0.42.2.

Metadata

CVE ID: CVE-2026-54555
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-15 19:04 UTC
Published: 2026-06-23 19:05 UTC
Last updated: 2026-06-23 19:05 UTC
Primary CWE: CWE-863
CWE-863: Incorrect Authorization
Vendor / Product: rtk-ai / rtk
Sources: cve.org · NVD

Severity & Metrics

7.8 HIGH CVSS 3.1

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products (1)

Vendor	Product	Platform	Versions
rtk-ai	rtk	—	< 0.42.2

Weakness (CWE)

CWE	Source	Description
CWE-863	cna	CWE-863: Incorrect Authorization

CVSS scores (1)

Score	Severity	Version	Source	Vector
7.8	HIGH	3.1	cna	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References (1)

https://github.com/rtk-ai/rtk/security/advisories/GHSA-7gxq-fvfc-g327 https://github.com/rtk-ai/rtk/security/advisories/GHSA-7gxq-fvfc-g327