high CVSS 7.7

CVE-2026-54018·Docker vulnerability

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the SafePlaywrightURLLoader implements a validate_url function to prevent SSRF attacks by checking the IP address of the user-provided URL. However, this validation is performed only on the initial URL. Since Playwright automatically follows HTTP redirects (301/302) by default, an attacker can bypass the validation by providing a safe URL that redirects to a restricted internal network address (e.g., localhost, Docker container network, or Cloud Metadata). This allows the application to access internal services despite ENABLE_RAG_LOCAL_WEB_FETCH being set to False This vulnerability is fixed in 0.9.6.

Severity
high
Software
Docker
Fixed in
0.9.6
Published
2026-06-23

Affected versions

Until: 0.9.6

Fixed in: 0.9.6

How to fix this CVE

Upgrade Docker to version 0.9.6 or later to patch the Server-Side Request Forgery (SSRF) vulnerability in the URL validation logic. The vulnerable SafePlaywrightURLLoader was allowing HTTP redirects to bypass IP address restrictions, potentially exposing internal services. Apply the update immediately across all Docker instances, especially those with RAG (Retrieval-Augmented Generation) web fetching capabilities enabled.

sudo dnf update docker-ce

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

POST /api/rag/web-fetch HTTP/1.1.*?url=http[s]?://[a-zA-Z0-9.-]+.*?(301|302|Location:.*?(localhost|127\.0\.0\.1|169\.254|10\.|172\.(1[6-9]|2[0-9]|3[01])\.|192\.168\.))

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Block requests to /api/rag/web-fetch or similar endpoints that include URL parameters containing internal IP ranges (127.0.0.1, 169.254.x.x, 10.x.x.x, 172.16-31.x.x, 192.168.x.x). Implement strict allowlist validation for redirects and reject HTTP 301/302 responses that point to non-whitelisted internal addresses.

How to check if you are affected

  1. Step 1: Check your installed Docker version with: docker --version
  2. Step 2: Verify if Open WebUI is running in your Docker environment: docker ps | grep open-webui
  3. Step 3: Review Docker container logs for suspicious URL requests: docker logs <container_id> | grep -iE '(redirect|http|url|ssrf|localhost|127\.0\.0\.1|169\.254)'
  4. Step 4: Confirm the patched version is installed by checking: docker inspect <container_id> | grep -i version

FAQ

What is CVE-2026-54018?

CVE-2026-54018 is an SSRF vulnerability in Open WebUI's SafePlaywrightURLLoader where URL validation checks can be bypassed using HTTP 301/302 redirects. An attacker can provide a legitimate URL that redirects to internal network addresses, allowing unauthorized access to services that should be restricted.

Is CVE-2026-54018 being actively exploited?

No, CVE-2026-54018 is not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog, and no public exploits are available.

What versions of Docker are affected by CVE-2026-54018?

All versions of Open WebUI prior to 0.9.6 are affected by this vulnerability. The issue impacts the SafePlaywrightURLLoader component used for RAG web fetching.

How do I check if my server is vulnerable to CVE-2026-54018?

Run: docker inspect <container_id> | grep -i 'open-webui' and check the version tag. If it's below 0.9.6, your system is vulnerable.

Does Defensia detect CVE-2026-54018?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-54018 will appear in your dashboard with remediation steps.

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References

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