Authenticated information disclosure via raw exception responses
Published Mar 28, 2026 · Updated Mar 28, 2026
Information disclosure in OpenUI 1.0 and 3.5-turb allows remote authenticated users to read server details through crafted API requests. The generic_exception_handler in backend/openui/server.py interpolates raw exception text into JSON error responses, while the APIStatusError path forwards upstream provider messages without sanitization. A session is required, but default local deployments issue one automatically; exposed data includes internal paths and, when provider errors contain them, API keys.
Summary
What happened
Information disclosure in OpenUI 1.0 and 3.5-turb allows remote authenticated users to read server details through crafted API requests. The generic_exception_handler in backend/openui/server.py interpolates raw exception text into JSON error responses, while the APIStatusError path forwards upstream provider messages without sanitization. A session is required, but default local deployments issue one automatically; exposed data includes internal paths and, when provider errors contain them, API keys.
The record
- CVE
- CVE-2026-4994
- Published
- Mar 28, 2026
- Updated
- Mar 28, 2026
- Vendor
- Weights & Biases
- Product
- OpenUI
- Classifications
- CWE-200, T1190
- Attack vector
- adjacent
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 28, 2026CVE publishedPublication date reported by the CVE source.
- Mar 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.0
- Affected versionversion=3.5-turb
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Verbose Error Messages Leak Server Internals and Upstream API Keys to Authenticated Usersproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo