CVE-2026-85621

Published: Sep 4, 2026Modified: Sep 8, 2026

6.9

Vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XShow less

Source: disclosure@vulncheck.com (Secondary)

Description

LobeChat (LobeHub) 2.2.1 does not properly verify inbound chat-platform webhook signatures in the QQ and Feishu adapters. The webhook route (/api/agent/webhooks/:platform) is unauthenticated by design and delegates verification to each adapter; the QQ adapter performs no Ed25519 signature verification on dispatched message events, and the Feishu adapter only performs an optional static-token comparison that is skipped when no token is configured (the default) and is not a body signature. An unauthenticated attacker who knows the public webhook URL can POST forged inbound messages with an attacker-chosen sender identity and arbitrary text, causing the bot owner's agent to process attacker-controlled input and treat the attacker as a trusted platform sender.