CVE-2026-82437 Apache Storm Logviewer: Log Access Controls Not Enforced by Logviewer
Attackers can read sensitive daemon logs and list all tenant logs in Apache Storm Logviewer due to missing authorization checks on specific endpoints.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-82437?
CVE-2026-82437 is a medium-severity missing authorization vulnerability in Apache Storm Logviewer, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Description
The Logviewer offers `logs.users` and `logs.groups` so operators can control who may read log content. For daemon logs those settings were not applied: the access decision combined the "this is a daemon log" flag with the authorizer result in a way that discarded the authorizer's answer whenever the flag was set, and the daemon log page and download endpoints reached the handler without consulting an authorizer at all. Any user able to pass the configured servlet filter could therefore read `nimbus.log`, `supervisor.log` and the other daemon logs on every reachable node, which contain other tenants' topology names, owners and configuration fragments.
The same advisory covers the log listing endpoints, which accepted a user argument and never applied it, so `/listLogs` and `/searchLogs` returned every tenant's topology and worker log file names regardless of the caller. That part is metadata only.
There was no configuration that closed either behaviour.
Mitigation
Upgrade to 3.1.0, where the daemon log paths evaluate the same configured user and group lists that the worker log paths already used, and the listing endpoints filter by the requesting user.
Users who cannot upgrade immediately should place the Logviewer behind a reverse proxy that restricts the daemon log endpoints, and should treat daemon log content as readable by any filter-authenticated user.
Credit
The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.
Weakness: CWE-862
Which versions are affected by CVE-2026-82437?
How do I fix CVE-2026-82437?
No fix has been published for CVE-2026-82437 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-82437 being exploited?
There is no known exploitation of CVE-2026-82437 in the wild and no public exploit code.
Sources
Also known as GHSA-mwq3-c685-c87r.