CVE-2026-85621

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory published 2026-09-04. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
60(Attend)
EG Risk 60/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
5%
KEV
Not listed

Published

September 4, 2026

Last Modified

September 8, 2026

Advisory Details (5)

Auto-updated Sep 4, 2026
No patch confirmed yet.
generic

LobeChat 2.2.1 Webhook Signature Verification Bypass QQ Feishu | Advisories | VulnCheck

https://www.vulncheck.com/advisories/lobechat-2.2.1-webhook-signature-verification-bypass-qq-feishu
generic

lobehub/packages/chat-adapter-feishu/src/adapter.ts at v2.2.15 · lobehub/lobehub · GitHub

https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-feishu/src/adapter.ts
generic

lobehub/packages/chat-adapter-qq/src/adapter.ts at v2.2.15 · lobehub/lobehub · GitHub

https://github.com/lobehub/lobehub/blob/v2.2.15/packages/chat-adapter-qq/src/adapter.ts
generic

GitHub - lobehub/lobehub: 🤯 LobeHub is your Chief Agent Operator, organizing your agents into 7×24 operations by hiring, scheduling, and reporting on your entire AI team. · GitHub

https://github.com/lobehub/lobehub
generic

Inbound chat-platform webhooks accept forged messages (no Ed25519 verification on QQ, optional/static token on Feishu) · Issue #16538 · lobehub/lobehub · GitHub

https://github.com/lobehub/lobehub/issues/16538

Vendor Advisories for CVE-2026-85621(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 46× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 21:29 UTCEG score recompute
  2. 2026-09-19 21:29 UTCGHSA enrichment
  3. 2026-09-18 21:22 UTCEG score recompute
  4. 2026-09-18 21:22 UTCGHSA enrichment
  5. 2026-09-18 19:28 UTCEPSS rescore
  6. 2026-09-17 20:24 UTCEG score recompute
  7. 2026-09-17 20:24 UTCGHSA enrichment
  8. 2026-09-17 19:32 UTCEPSS rescore
  9. 2026-09-16 19:15 UTCEG score recompute
  10. 2026-09-16 19:15 UTCGHSA enrichment
  11. 2026-09-16 14:09 UTCEPSS rescore
  12. 2026-09-16 05:15 UTCEPSS rescore
  13. 2026-09-15 19:09 UTCEG score recompute
  14. 2026-09-15 19:08 UTCGHSA enrichment
  15. 2026-09-15 03:12 UTCEPSS rescore
  16. 2026-09-15 03:12 UTCEPSS rescore
  17. 2026-09-14 19:01 UTCGHSA enrichment
  18. 2026-09-13 18:54 UTCEG score recompute
  19. 2026-09-13 18:54 UTCGHSA enrichment
  20. 2026-09-12 18:47 UTCEG score recompute
  21. 2026-09-12 18:47 UTCGHSA enrichment
  22. 2026-09-11 18:40 UTCEG score recompute
  23. 2026-09-11 18:40 UTCGHSA enrichment
  24. 2026-09-11 14:53 UTCEPSS rescore
  25. 2026-09-11 14:53 UTCEPSS rescore
Show 21 more
  1. 2026-09-10 18:33 UTCEG score recompute
  2. 2026-09-10 18:33 UTCGHSA enrichment
  3. 2026-09-09 18:25 UTCEG score recompute
  4. 2026-09-09 18:25 UTCGHSA enrichment
  5. 2026-09-08 22:01 UTCEPSS rescore
  6. 2026-09-08 18:17 UTCEG score recompute
  7. 2026-09-08 18:17 UTCGHSA enrichment
  8. 2026-09-08 17:04 UTCEG score recompute
  9. 2026-09-08 17:03 UTCGHSA enrichment
  10. 2026-09-08 16:21 UTCEG score recompute
  11. 2026-09-08 16:20 UTCGHSA enrichment
  12. 2026-09-07 15:46 UTCGHSA enrichment
  13. 2026-09-06 15:40 UTCEG score recompute
  14. 2026-09-06 15:40 UTCGHSA enrichment
  15. 2026-09-06 13:48 UTCEPSS rescore
  16. 2026-09-05 15:33 UTCEG score recompute
  17. 2026-09-05 15:33 UTCGHSA enrichment
  18. 2026-09-05 15:31 UTCEPSS rescore
  19. 2026-09-04 15:25 UTCEG score recompute
  20. 2026-09-04 14:46 UTCEG score recompute
  21. 2026-09-04 14:44 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-85621?
CVE-2026-85621 is a medium vulnerability published on September 4, 2026. 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…
When was CVE-2026-85621 disclosed?
CVE-2026-85621 was first published in the National Vulnerability Database on September 4, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-85621 actively exploited?
CVE-2026-85621 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 94.9% of all scored CVEs.
What is the CVSS score of CVE-2026-85621?
CVE-2026-85621 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-85621?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-85621, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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