# CVE-2026-54555: rtk: Permission-gate bypass in rtk rewrite auto-allow via unsplit shell separators

> Attackers can bypass permission gates in rtk by hiding commands behind shell separators, allowing unauthorized execution of arbitrary commands.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 23 Jun 2026
- **Updated:** 24 Jun 2026
- **Also known as:** GHSA-7gxq-fvfc-g327

## What is CVE-2026-54555?

CVE-2026-54555 is a high-severity vulnerability in rtk-ai rtk, published on 23 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official 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.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-54555?


## How do I fix CVE-2026-54555?

No fix has been published for CVE-2026-54555 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-54555 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54555 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-54555 and fix it if it is affected.

What it is: CVE-2026-54555 is a high-severity vulnerability in rtk-ai rtk, published on 23 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54555 exists.

Affected product: rtk-ai rtk. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-54555/ (Markdown: https://insights.sbomify.com/CVE-2026-54555/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-54555
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-54555
- OSV: https://osv.dev/vulnerability/CVE-2026-54555

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-54555/
Summaries are generated and may contain mistakes; the official description above is the record.