CVE-2026-56837 (GCVE-0-2026-56837)
Vulnerability from cvelistv5
Published
2026-10-23 11:57
Modified
2026-10-23 21:05
CWE
  • CWE-287 - Improper Authentication
  • CWE-306 - Missing Authentication for Critical Function
  • CWE-347 - Improper Verification of Cryptographic Signature
Summary
PraisonAI is a multi-agent teams system. From version 4.6.56 to before version 4.6.59, PraisonAI's LinearBot starts a public webhook listener on 0.0.0.0 and treats LINEAR_WEBHOOK_SECRET as optional. When the secret is absent, startup only logs a warning and _handle_webhook() skips Linear-Signature verification entirely. An unauthenticated network caller who can reach the webhook endpoint can submit a forged Linear-Event: AgentSession request. The forged request is parsed, scheduled for background processing, dispatched to _handle_agent_session(), and passed into BotSessionManager.chat(). The bot then attempts to post the agent response back to Linear under the configured bot token. The PoV is offline and deterministic. It does not contact Linear. It calls the webhook handler directly, monkey-patches the outbound Linear comment path, and proves both sides of the boundary. This issue has been patched in version 4.6.59.
Impacted products
Vendor Product Version
MervinPraison PraisonAI Version: >= 4.6.56, < 4.6.59
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Show details on NVD website


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