What is CVE-2026-56399?

CVE-2026-56399 is a medium-severity vulnerability in Open-Webui, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.0/10. Published 2026-06-30.

How severe is CVE-2026-56399?

Medium severity. CVSS v3 base score is 5.0 out of 10.

SSRF in Open-Webui

CVE-2026-56399

Open WebUI before 0.6.27 contains a server-side request forgery vulnerability in the /api/v1/retrieval/process/web endpoint that allows authenticated users to bypass SSRF protections. Attackers can manipulate URL parameters with location redirect headers to access internal services and potentially execute commands via instance secrets.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2026-06-30 · last modified 2026-07-02.

CVSS v3 metric

CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (36.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 36.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Open-Webui — versions 0, 0.6.27

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

github.com/open-webui/open-webui/security/advisories/GHSA-82r6-c5jm-f3mw (vendor-advisory)
github.com/open-webui/open-webui/commit/02238d3113e966c353fce18f1b65117380896774 (patch)
www.vulncheck.com/advisories/open-webui-server-side-request-forgery-via-locatio… (third-party-advisory)

Frequently asked questions

What is CVE-2026-56399?: CVE-2026-56399 is a medium-severity vulnerability in Open-Webui, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.0/10. Published 2026-06-30.
How severe is CVE-2026-56399?: Medium severity. CVSS v3 base score is 5.0 out of 10.