Message forgery and deletion via missing authorship checks
Published Aug 4, 2026 · Updated Aug 4, 2026
Missing authorization in Open WebUI 0.5.0 through 0.10.2 allows remote authenticated users to alter or delete other users' channel messages. The standard-channel update and delete handlers in backend/open_webui/routers/channels.py check channel write access but not message authorship. Channels must be enabled, and the account must have write access to a standard channel; successful requests forge content under another author's identity or permanently delete it.
Summary
What happened
Missing authorization in Open WebUI 0.5.0 through 0.10.2 allows remote authenticated users to alter or delete other users' channel messages. The standard-channel update and delete handlers in backend/open_webui/routers/channels.py check channel write access but not message authorship. Channels must be enabled, and the account must have write access to a standard channel; successful requests forge content under another author's identity or permanently delete it.
The record
- CVE
- CVE-2026-70481
- Published
- Aug 4, 2026
- Updated
- Aug 4, 2026
- Vendor
- Open WebUI
- Product
- Open WebUI
- Classifications
- CWE-284, CWE-862, T1565.001
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 4, 2026CVE publishedPublication date reported by the CVE source.
- Aug 4, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 0.5.0, < 0.11.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- CVE-2026-70481 end-to-end channel-message exploit scriptsfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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