Auth bypass in Open-Webui
CVE-2026-70481
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.0, the standard channel message update and delete handlers accepted any caller holding write access on the channel without checking that the caller wrote the message. Because write access is the same grant a member needs to post, any ordinary participant in a shared standard channel could rewrite or permanently delete another participant message, while group and direct message handlers enforced authorship. This issue is fixed in 0.11.0.
EPSS: 0.003 (22.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.
Affected products
- Open-webui — versions >= 0.5.0, < 0.11.0
- Openwebui Open_webui
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-70481?
- CVE-2026-70481 is a medium-severity vulnerability in Open-Webui, classified under Improper Access Control. CVSS score: 5.4/10. Published 2026-08-04.
- How severe is CVE-2026-70481?
- Medium severity. CVSS v3 base score is 5.4 out of 10.
- Is CVE-2026-70481 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.