[<prev] [next>] [day] [month] [year] [list]
Message-ID: <9f53aa48-8829-b64a-1d12-cf10df747efc@apache.org>
Date: Sun, 13 Sep 2026 05:45:54 +0000
From: Richard Zowalla <rzo1@...che.org>
To: oss-security@...ts.openwall.com
Subject: CVE-2026-82429: Apache Storm Worker Launcher: Local Privilege
Escalation to Root via a Time-of-Check Race in the Worker Launcher
Severity: important
Affected versions:
- Apache Storm Worker Launcher (org.apache.storm:storm-core) 3.0.0 before 3.1.0
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.
Credit:
The ASF using Claude Agents (finder)
References:
https://storm.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-82429
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
