CVE-2026-54007 json
Open WebUI: Cross-origin postMessage confirmation bypass via action:submit
published 2026-06-17 4 mo ago modified 2026-07-20 3 mo ago also GHSA-3vv5-8xxp-4f55 , PYSEC-2026-2695 , EUVD-2026-38536
- cvss
- 6.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the chat message listener allows non-same-origin input:prompt and action:submit messages, so an external site can set prompt text and trigger submitPrompt() in an authenticated victim session. I validated this with a cross-origin attacker page that auto-posted messages and caused unauthorized POST /api/v1/chats/new and POST /api/chat/completions requests containing attacker-controlled prompts. This enables cross-site forced actions and model/tool execution under victim privileges without consent. This vulnerability is fixed in 0.9.6.
Patch / fix
- pypi open-webui 0.9.6
- openwebui open_webui 0.9.6
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/open-webui/open-webui/security/advisories/GHSA-3vv5-8xxp-4f55 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 7.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | open-webui | <0.9.6 |
0.9.6 |
Affected products
- open-webui open-webui
Classification
- Weakness
-
- CWE-346 Origin Validation Error
References
-
github.com
/open-webui/open-webui/security/advisories/GHSA-3vv5-8xxp-4f55
exploit, web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-54007
advisory
-
github.com
/advisories/GHSA-3vv5-8xxp-4f55
advisory
-
github.com
/open-webui/open-webui
package
-
github.com
/pypa/advisory-database/tree/main/vulns/open-webui/PYSEC-2026-2695.yaml
web
-
pypi.org
/project/open-webui
web, package
Sources
- CVE List CVE-2026-54007
- GitHub Advisory GHSA-3vv5-8xxp-4f55
- NVD CVE-2026-54007
- OSV PYSEC-2026-2695
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.