GHSA-73x5-h92w-xc2j is a low-severity (CVSS 3.1) CWE-639 vulnerability in open-webui. O3 Security confirms whether GHSA-73x5-h92w-xc2j is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Open WebUI: Private channel messages can be disclosed through cross-channel thread parent_id binding
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-73x5-h92w-xc2j.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-73x5-h92w-xc2j plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 0 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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
Summary
A normal authenticated user can read the content of a message in a private channel they do not belong to. GET /api/v1/channels/{id}/messages/{message_id}/thread authorizes the caller against the URL channel, but the underlying thread lookup loads the thread parent by id and returns it without verifying the parent belongs to that channel. By requesting a thread in a channel they can access while supplying a victim channel's message id as the thread root, the attacker receives the victim message — content, channel id, and author.
Affected component
backend/open_webui/models/messages.py—get_messages_by_parent_id()backend/open_webui/routers/channels.py—get_channel_thread_messages()(read),new_message_handler()(parent/reply binding on write)
Root cause
get_messages_by_parent_id(channel_id, parent_id) filters the thread replies by channel_id, but loads the thread parent by id alone and appends it without requiring parent.channel_id == channel_id:
message = await db.get(Message, parent_id) # loaded by id only — no channel binding
if not message:
return []
# replies are filtered by channel_id ...
if len(all_messages) < limit:
all_messages.append(message) # parent appended unconditionally
get_channel_thread_messages() authorizes only the URL channel, then calls get_messages_by_parent_id(id, message_id) with the caller-supplied message_id. The reply insert path (new_message_handler → insert_new_message) also stored a caller-supplied parent_id without binding it to the channel.
Impact
A non-member can disclose the content (plus channel id and author metadata) of a private-channel message whose id they know or obtain. Direct reads of the victim channel/message/thread return 403; the disclosure is via the thread parent of a channel the attacker can access. Read-only, one message per known id.
Proof of Concept
(reporter) Validated on v0.9.6: GET /channels/{attacker_channel}/messages/{victim_message_id}/thread returned the victim's private message — content, victim channel id, and author — although direct reads of the victim channel returned 403.
Fix
Bind the thread parent to the requested channel: get_messages_by_parent_id returns [] unless the parent exists and parent.channel_id == channel_id. Defence-in-depth on the write path: new_message_handler rejects a supplied parent_id/reply_to_id whose message does not belong to the URL channel.
Affected / Patched
- Affected:
< 0.10.0(last affected release 0.9.6) - Patched: v0.10.0 (PR #25766).
get_messages_by_parent_idbinds the thread parent to the requested channel (returns[]unlessparent.channel_id == channel_id), andnew_message_handlerrejects a caller-suppliedparent_id/reply_to_idwhose message does not belong to the channel.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | open-webui | all versions | 0.10.0 |
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 0.10.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-73x5-h92w-xc2j 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 GHSA-73x5-h92w-xc2j 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 GHSA-73x5-h92w-xc2j. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-73x5-h92w-xc2j in your dependencies?
O3 detects GHSA-73x5-h92w-xc2j across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.