CVE-2026-59218 Open WebUI: Account enumeration via observable login timing discrepancy

What is CVE-2026-59218?

CVE-2026-59218 is a medium-severity vulnerability in Openwebui Open Webui, published on 9 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, the /api/v1/auths/signin endpoint looked users up by email and only ran bcrypt password verification when a credential existed, making registered-account attempts measurably slower than missing-email attempts and allowing unauthenticated account enumeration. This issue is fixed in version 0.10.0.

Weakness: CWE-208

Which versions are affected by CVE-2026-59218?

3 open source packages ship an affected version, including open-webui. It affects 1 product.

Products include Openwebui Open Webui.

How do I fix CVE-2026-59218?

Upgrade open-webui to 0.10.0 or later.

Is CVE-2026-59218 being exploited?

There is no known exploitation of CVE-2026-59218 in the wild and no public exploit code.

Other vulnerabilities in Openwebui Open Webui

• CVE-2026-44551 Open WebUI: LDAP Empty Password Authentication Bypass Critical 9.1
• CVE-2026-56400 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation Critical 9.0
• CVE-2024-8017 Cross-site Scripting (XSS) in open-webui/open-webui Critical 9.0
• CVE-2026-45672 Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed High 8.8
• CVE-2026-87995 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin High 8.7

All Openwebui Open Webui vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-7rw5-9f7q-xj36, PYSEC-2026-3594.