CVE-2026-44571 — open-webui
MEDIUMCVE-2026-44571 is a medium-severity (CVSS 6.5) CWE-862 vulnerability in open-webui. A fix is available for open-webui — see the affected versions and patch details below.
Open WebUI: Improper Authorization in Standard Channels Allows Message Updates with Read Permission
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 CVE-2026-44571.
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
CVE-2026-44571 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 378,567 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
Vulnerability Description
In standard channels (i.e., channels whose channel.type is neither group nor dm), the endpoint
POST /api/v1/channels/{channel_id}/messages/{message_id}/update can be accessed with read permission only.
When access_control is set to None, the authorization check has_access(..., type="read") evaluates to True, allowing users who are not the message owner to update messages.
As a result, unauthorized modification of other users’ messages is possible.
Attack Prerequisites
- The attacker is an authenticated user (role
useror higher) - The target channel is a standard channel (i.e., not
groupordm) access_controlisNoneor allowsreadaccess- The attacker can obtain the target
message_id(e.g., via the channel’s message list)
Attack Scenario
-
The attacker (User B) retrieves another user’s
message_idfrom the message list in a standard channel -
The attacker sends a request to
POST /api/v1/channels/{channel_id}/messages/{message_id}/update -
The message authored by another user (User A) is successfully updated
Potential Impact
- Unauthorized modification of other users’ messages (violation of data integrity)
Steps to Reproduce
- Log in as an administrator
- Create User A
- Create User B
- Log in as User A
- Log in as User B
- As the administrator, create a new channel
- As User A, post a new message in the channel
- As User B, edit User A’s message
- Confirm that User A’s message has been modified without authorization
Affected Files and Line Numbers
-
backend/open_webui/routers/channels.py:1417–1460The authorization check in
update_message_by_idallows access with read permission -
backend/open_webui/utils/access_control.py:124–135When
access_control=Noneandstrict=True, read access is permitted -
backend/open_webui/models/messages.py:341–358The update logic does not enforce any message ownership check
Recommended Mitigation
Update the condition in
backend/open_webui/routers/channels.py:1451–1456
by changing the permission check from read to write, so that only administrators, message owners, or users with write permission can update messages.
Proposed Changes
-
For standard channels, change the update permission requirement from
has_access(..., type="read")tohas_access(..., type="write") -
Preserve the existing ownership check (
message.user_id == user.id)
AI Usage
- Translation from Japanese to English
- CWE classification and assessment
- Affected Files and Line Numbers
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | open-webui | all versions | 0.8.6pip install --upgrade 'open-webui==0.8.6' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for open-webui, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update open-webui to 0.8.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44571 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-44571 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-44571. 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-2026-44571 in your dependencies?
O3 Security finds CVE-2026-44571 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.