CVE-2026-54017 | Open WebUI: Path traversal / SSRF in terminal server proxy via encoded path traversal

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the terminal-server reverse proxy in `backend/open_webui/routers/terminals.py` does not fully confine the user-controlled `path` segment before forwarding it to an admin-configured terminal server. An authenticated user who has been granted access to a terminal server can craft `path` values containing encoded `../` traversal sequences that escape the intended path (or policy) scope on that server, reaching unintended endpoints and files on the terminal-server host. Where the terminal server fans requests out to internal services, this also gives SSRF-style reach into those services. This is a separate code path from the `/api/v1/retrieval/process/web` SSRF (GHSA-c6xv-rcvw-v685), with its own input. Two distinct vectors are consolidated here: first, raw path forwarding / single-encoded traversal (original report); and second, a bypass of the subsequently-added `_sanitize_proxy_path` mitigation using double-encoded dots (`%252e%252e`). The attacker-controlled input is the request `path`, supplied by the non-admin user, not anything an administrator configures, so this is not an admin-trust / Rule-9 situation. Version 0.9.6 fixes the issue.

Published: 2026-06-18 Last update: 2026-06-24 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-54017 is rated Moderate Risk (41.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.37%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-54017

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-23 0.04% 0.37% +0.33%
2 2026-06-12 0.04%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-54017

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.7 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.1 4.0 [email protected]

Weakness enumeration for CVE-2026-54017

GitHub Security Advisory for CVE-2026-54017

GHSA-r2wg-2mcr-66rv · Severity: high · Ecosystem: pip — Open WebUI: Path traversal / SSRF in terminal server proxy via encoded path traversal

Affected software / configurations for CVE-2026-54017

Vendor Product Version Raw CPE
openwebui open_webui < 0.9.6 cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

References for CVE-2026-54017

cvelogic Threat Intelligence