# CVE-2026-18157: Yggdrasil-worker-package-manager: yggdrasil-worker-package-manager: remote code execution via apt argument injection

> A local attacker can achieve root code execution by injecting arguments into apt-get via crafted package names in the Yggdrasil worker package manager.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 Jul 2026
- **Updated:** 31 Jul 2026
- **Also known as:** GHSA-f9rr-qg3x-wq4m

## What is CVE-2026-18157?

CVE-2026-18157 is a high-severity command injection vulnerability in Red Hat Enterprise Linux 10, published on 31 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in yggdrasil-worker-package-manager. A local attacker with existing access to the system could exploit an argument injection vulnerability in the APT backend. This allows specially crafted package names, which begin with a hyphen, to be misinterpreted as command options by apt-get. Successful exploitation could lead to remote code execution (RCE) with root privileges, enabling the attacker to fully compromise the system's integrity, confidentiality, and availability.

Weakness: CWE-88 (Improper Neutralization of Argument Delimiters in a Command)

## Which versions are affected by CVE-2026-18157?


## How do I fix CVE-2026-18157?

No fix has been published for CVE-2026-18157 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-18157 being exploited?

There is no known exploitation of CVE-2026-18157 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-18157 and fix it if it is affected.

What it is: CVE-2026-18157 is a high-severity command injection vulnerability in Red Hat Enterprise Linux 10, published on 31 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-18157 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. 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-2026-18157/ (Markdown: https://insights.sbomify.com/CVE-2026-18157/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-18157
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-18157
- OSV: https://osv.dev/vulnerability/CVE-2026-18157

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-18157/
Summaries are generated and may contain mistakes; the official description above is the record.