How severe is CVE-2026-28786?

CVE-2026-28786 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-28786 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-28786?

CVE-2026-28786 affects Openwebui Open Webui. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-28786?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-28786 have an EU (EUVD) identifier?

Yes. CVE-2026-28786 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16480.

When was CVE-2026-28786 published?

CVE-2026-28786 was published on 2026-03-27 and last updated on 2026-06-17.

CVE-2026-28786

CVE-2026-28786 is a medium-severity vulnerability in Openwebui Open Webui with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16480
Weakness: CWE-22
Affected product: Openwebui Open Webui
Published: 2026-03-27
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-28786?: 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.
How severe is CVE-2026-28786?: CVE-2026-28786 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-28786 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-28786?: CVE-2026-28786 affects Openwebui Open Webui. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-28786?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-28786 have an EU (EUVD) identifier?: Yes. CVE-2026-28786 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16480.
When was CVE-2026-28786 published?: CVE-2026-28786 was published on 2026-03-27 and last updated on 2026-06-17.

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-vvxm-vxmr-624h

Affected products (1)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

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