# CVE-2026-85621

## Summary

- **CVE ID:** CVE-2026-85621
- **Severity:** MEDIUM
- **CVSS Score:** 6.9 (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)
- **CWE:** CWE-345
- **Published:** Sep 4, 2026
- **Last Modified:** Sep 8, 2026

## 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.

## Affected Products

- lobehub — lobehub (0)

## References

- [CNA](https://github.com/lobehub/lobehub/issues/16538)
- [CNA](https://github.com/lobehub/lobehub)
- [CNA](https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-qq/src/adapter.ts)
- [CNA](https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-feishu/src/adapter.ts)
- [CNA](https://www.vulncheck.com/advisories/lobechat-2.2.1-webhook-signature-verification-bypass-qq-feishu)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.16%
- **EPSS Percentile:** 5.0

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._