CVE-2026-85621 (GCVE-0-2026-85621)

Vulnerability from cvelistv5 – Published: 2026-09-04 14:32 – Updated: 2026-09-08 16:54
VLAI
Title
LobeChat 2.2.1 Webhook Signature Verification Bypass QQ Feishu
Summary
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.
Severity
6.9 (Medium)
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
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 16:53 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
Assigner
References
Impacted products
Vendor Product Version CPE status
lobehub lobehub Affected: 0 , ≤ 2.2.15 (custom)
    cpe:2.3:a:lobehub:lobehub:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-01 00:00
Credits
George Chen
Show details on NVD website
To clipboard 

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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