{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "last_affected": "2.2.15"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "5cb99eecff280c2563de99f8afd1bb7f536db45c"
            }
          ],
          "repo": "https://github.com/lobehub/lobehub",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-345"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85621.json"
  },
  "details": "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.",
  "id": "CVE-2026-85621",
  "modified": "2026-09-06T03:30:15.028572864Z",
  "published": "2026-09-04T14:32:12.595Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85621.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-85621"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/lobechat-2.2.1-webhook-signature-verification-bypass-qq-feishu"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/lobehub/lobehub/issues/16538"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/lobehub/lobehub"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-feishu/src/adapter.ts"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-qq/src/adapter.ts"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "LobeChat 2.2.1 Webhook Signature Verification Bypass QQ Feishu"
}