CVE-2026-70481

MEDIUM

Open WebUI: Any member with write access to a standard channel can edit or delete other members' messages

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-70481. PoCs published by Foxer131.

AI-analyzed exploit summary This repository contains a functional exploit for CVE-2026-70481, demonstrating an authentication bypass in channel message manipulation. The PoC allows a standard user with write access to edit, delete, pin, and forge messages authored by other users in standard channels, including payload injection and history destruction.

Description

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.0, the standard channel message update and delete handlers accepted any caller holding write access on the channel without checking that the caller wrote the message. Because write access is the same grant a member needs to post, any ordinary participant in a shared standard channel could rewrite or permanently delete another participant message, while group and direct message handlers enforced authorship. This issue is fixed in 0.11.0.

Exploits (1)

github WORKING POC
by Foxer131 · pythonpoc
https://github.com/Foxer131/CVE-2026-70481

This repository contains a functional exploit for CVE-2026-70481, demonstrating an authentication bypass in channel message manipulation. The PoC allows a standard user with write access to edit, delete, pin, and forge messages authored by other users in standard channels, including payload injection and history destruction.

Classification
Working Poc 99%
Attack Type
Auth Bypass
Complexity
Moderate
Reliability
Reliable
Target: backend/open_webui (v0.10.2)
Auth required
Prerequisites: Standard user account with write access to the target channel · Target channel must be a standard channel (not group/DM) · Victim must have existing messages in the channel
mistral-large-3 · analyzed Aug 05, 2026 Full analysis →

Scores

CVSS v3 5.4
EPSS 0.0030
EPSS Percentile 22.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-284 CWE-862
Status published
Products (2)
open-webui/open-webui >= 0.5.0, < 0.11.0
pypi/open-webui 0.5.0 - 0.11.0PyPI
Published Aug 04, 2026
Tracked Since Aug 05, 2026