CVE-2026-44561
MEDIUMCVE-2026-44561 is a medium-severity (CVSS 5.4) vulnerability in open-webui. O3 Security confirms whether CVE-2026-44561 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Open WebUI: Deactivated Channel Members Retain Full Access to Group/DM Channels
Real-World Exposure
open-webuiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the is_user_channel_member function checks whether a ChannelMember row exists but does not check the is_active field. When a user is deactivated from a group or DM channel (removed by the channel owner, or leaves voluntarily), their membership row persists with is_active=False and status='left'. Because the authorization check ignores this field, the deactivated user retains full read and write access to the channel via direct API calls. This vulnerability is fixed in 0.9.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | open-webui | all versions | 0.9.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for open-webui. 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.
Fix
Update open-webui to 0.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44561 is resolved across your whole dependency graph.
Workarounds
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-2026-44561 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-2026-44561. 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-2026-44561 in your dependencies?
O3 detects CVE-2026-44561 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.