Medium severity · published Mar 26, 2026
CVE-2026-28786
Open WebUI vulnerable to Path Traversal in `POST /api/v1/audio/transcriptions`
4.3
CVSS
0.6%
EPSS
No
On KEV
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to version 0.8.6, an unsanitized filename field in the speech-to-text transcription endpoint allows any authenticated non-admin user to trigger a `FileNotFoundError` whose message — including the server's absolute `DATA_DIR` path — is returned verbatim in the HTTP 400 response body, confirming information disclosure on all default deployments. Version 0.8.6 patches the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
open-webui · open-webui
< 0.8.6 · source: vendor
OW
Open Webui · Openwebui
before 0.8.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-28786
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-28786
Exploit
https://github.com/open-webui/open-webui/security/advisories/GHSA-vvxm-vxmr-624h
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