# CVE-2026-82430: Apache Storm Worker Launcher: Local Privilege Escalation to Root via Container Command Files Chowned to the Tenant

> A race condition in Apache Storm's worker launcher allows local attackers to escalate privileges to root by modifying command files during container startup.

- **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:** 14 Sep 2026
- **Updated:** 14 Sep 2026
- **Also known as:** GHSA-pjcp-2m43-fmv9

## What is CVE-2026-82430?

CVE-2026-82430 is a high-severity vulnerability in Apache Storm Worker Launcher, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Description

When launching a Docker or OCI worker, the setuid-root `worker-launcher` first changes ownership of the
entire worker directory to the untrusted topology user, and only afterwards reads and acts on the command
file that the supervisor wrote into that same directory. The file is opened without `O_NOFOLLOW` and without
re-verifying its owner, so between the ownership change and the read the tenant can replace its contents.

For the Docker path the parsed command is executed with real uid 0, and the command sanitiser is not a
privilege boundary: it admits `-v` with an arbitrary source, `--device`, `--cap-add`, `--security-opt`,
`--user` and `--net`, and copies positional arguments through verbatim. A rewritten file therefore yields an
attacker-authored, root-equivalent container invocation with the host filesystem available.

For the OCI path the same rewrite window applies, and mount validation is structural only, with no
source or destination allow-list, so arbitrary host paths can be bind-mounted read-write into the
container. The `username` field of the command file is likewise attacker-settable and is checked only
against non-root and minimum-uid rules, permitting execution as another tenant's uid.

Mitigation

Upgrade to 3.1.0, where the command file is validated before the ownership change and re-verified on open,
and where mount sources and destinations are constrained by configuration.

Users who cannot upgrade immediately should disable Docker and OCI worker isolation, or restrict topology
submission on affected supervisors to trusted principals. Note that the launcher must be rebuilt and
reinstalled after upgrading.

Credit

The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2026-82430?


## How do I fix CVE-2026-82430?

No fix has been published for CVE-2026-82430 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-82430 being exploited?

There is no known exploitation of CVE-2026-82430 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82430 and fix it if it is affected.

What it is: CVE-2026-82430 is a high-severity vulnerability in Apache Storm Worker Launcher, published on 14 Sep 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-2026-82430 in the wild and no public exploit code.

Affected product: Apache Storm Worker Launcher. 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-2026-82430/ (Markdown: https://insights.sbomify.com/CVE-2026-82430/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82430
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82430
- OSV: https://osv.dev/vulnerability/CVE-2026-82430

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82430/
Summaries are generated and may contain mistakes; the official description above is the record.