CVE-2026-82429
CVE-2026-82429 is a CWE-367 vulnerability. O3 Security confirms whether CVE-2026-82429 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Description The setuid-root `worker-launcher` binary adjusts ownership and permissions of worker directories by walking the tree with FTS and calling `lchown` and `chmod` on each entry's…
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-82429.
Description
Description
The setuid-root worker-launcher binary adjusts ownership and permissions of worker directories by walking
the tree with FTS and calling lchown and chmod on each entry's full pathname while running with an
effective uid of 0. Both syscalls re-resolve the path at the time of the call, after FTS has classified the
entry, and the trees being walked are owned and writable by the untrusted topology user.
A tenant running code on a supervisor node could therefore replace an intermediate directory component with
a symbolic link between classification and the privileged operation, redirecting the root-owned lchown or
chmod at an arbitrary file on the host. The operation is repeatable at will, since crashing a worker
forces a relaunch and blob updates re-run the walk, so a failed attempt costs the attacker nothing.
This crosses the boundary that supervisor.run.worker.as.user and container isolation are intended to
enforce. It is the same defect class as the Hadoop container-executor issues from which this code derives.
Mitigation
Upgrade to 3.1.0, where the privileged walk operates on file descriptors it has already stat'd rather than on pathnames re-resolved at call time.
Users who cannot upgrade immediately should not run untrusted topology code on supervisors configured with
supervisor.run.worker.as.user, since the launcher is the boundary being crossed. Note that the launcher
must be rebuilt and reinstalled after upgrading; replacing the Java artifacts alone is not sufficient.
Credit
The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-82429 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-82429 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-82429. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-82429 in your dependencies?
O3 detects CVE-2026-82429 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.