Open WebUI Unauthenticated Multipart Boundary Denial of Service (DoS) Vulnerability in api/chat/fileGHSA-6wj5-5pgr-jwq8
HIGHFix: open-webui/open-webui@f311c03GHSA-6wj5-5pgr-jwq8 is a high-severity (CVSS 7.5) vulnerability in open-webui. A fix is available for open-webui — see the affected versions and patch details below.
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
A vulnerability in open-webui/open-webui version 79778fa allows an attacker to cause a Denial of Service (DoS) by uploading a file with a malformed multipart boundary. By appending a large number of characters to the end of the multipart boundary, the server continuously processes each character, rendering the application inaccessible. This issue can prevent all users from accessing the application until the server recovers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | open-webui | all versions | 0.4.7pip install --upgrade 'open-webui==0.4.7' |
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 0.4.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6wj5-5pgr-jwq8 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is GHSA-6wj5-5pgr-jwq8 in your dependencies?
Find it across PyPI, including transitive dependencies.