CVE-2026-45387 json
Open WebUI: Sharing models for others to use (read permission) also exposes model details (system prompt leakage)
published 5mo ago modified 3mo ago also EUVD-2026-30628 , GHSA-h2cw-7qw9-56xr , PYSEC-2026-2728
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, when setting model permissions so that a group has read access to it, intending for other users to use it, those users also can read the model's system prompt. However users may consider their system prompt confidential, so this is considered a security issue. This vulnerability is fixed in 0.9.5.
Patch / fix
- pypi open-webui 0.9.5
- openwebui open_webui 0.9.5
Is CVE-2026-45387 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/open-webui/open-webui/security/advisories/GHSA-h2cw-7qw9-56xr referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
| GitHub | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
| OSV | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | open-webui | <0.9.5 |
0.9.5 |
Affected products
- open-webui open-webui
Classification
- Weakness
-
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
References
-
github.com
/open-webui/open-webui/security/advisories/GHSA-h2cw-7qw9-56xr
exploit, web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-45387
advisory
-
github.com
/open-webui/open-webui
package
-
github.com
/open-webui/open-webui/releases/tag/v0.9.5
web
-
pypi.org
/project/open-webui
package
-
github.com
/advisories/GHSA-h2cw-7qw9-56xr
advisory
Sources
- CVE List CVE-2026-45387
- GitHub Advisory GHSA-h2cw-7qw9-56xr
- NVD CVE-2026-45387
- OSV PYSEC-2026-2728
Fencer Intel 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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.