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CVE-2026-56837— PraisonAI LinearBot processes unsigned webhooks when LINEAR_WEBHOOK_SECRET is missing

Quick assessment

Affected
MervinPraison PraisonAI
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

PraisonAI 是一个多智能体团队系统。在版本 4.6.56 至 4.6.59（不含）之间，PraisonAI 的 LinearBot 会在 0.0.0.0 上启动一个公共 Webhook 监听器，并将 LINEAR_WEBHOOK_SECRET 视为可选配置。当该密钥缺失时，系统启动时仅记录一条警告，且 _handle_webhook() 函数完全跳过对 Linear-Signature 的验证。任何能够访问该 Webhook 端点的未授权网络调用者均可提交伪造的 Linear-Event: AgentSes

CVSS 8.6 · High
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I. Basic Information for CVE-2026-56837

Vulnerability Information
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Vulnerability Title
PraisonAI LinearBot processes unsigned webhooks when LINEAR_WEBHOOK_SECRET is missing
Source: CVE Program / CVE List V5
Vulnerability Description
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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L
Source: CVE Program / CVE List V5
Vulnerability Type
认证机制不恰当
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
MervinPraison PraisonAI >= 4.6.56, < 4.6.59 -

II. Public POCs for CVE-2026-56837

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III. Intelligence Information for CVE-2026-56837

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Other References for CVE-2026-56837 (1)

Same Patch Batch · MervinPraison · 2026-10-23 · 16 CVEs total

CVE-2026-57116 9.8 CRITICAL PraisonAI: AgentOS remains unauthenticated after GHSA-pm96 patched version and allows remo
CVE-2026-56832 8.8 HIGH PraisonAI DiscordApproval accepts unrelated channel messages as dangerous-tool approvals
CVE-2026-56840 8.8 HIGH PraisonAI: HTTPApproval dashboard renders tool arguments as raw HTML, allowing approval-pa
CVE-2026-57117 8.8 HIGH PraisonAI: Compute-bridged file tools allow shell command injection
CVE-2026-57144 8.8 HIGH PraisonAI SandlockSandbox falls back to unrestricted subprocess execution when Landlock is
CVE-2026-56835 8.3 HIGH PraisonAI Slack app_mention bypasses configured user/channel authorization
CVE-2026-56836 8.2 HIGH PraisonAI recipe serve Typer command bypasses the non-localhost authentication guard
CVE-2026-57113 8.1 HIGH PraisonAI GitHub template cache path traversal allows outside-cache file write and directo
CVE-2026-57121 8.1 HIGH PraisonAI: Missing ownership check on DELETE endpoints allows members to delete others' co
CVE-2026-56838 7.8 HIGH PraisonAI recipe.run_stream skips dangerous-tool policy enforcement
CVE-2026-57142 7.8 HIGH PraisonAI recipe workflow policy can be bypassed by declaring and YAML-approving dangerous
CVE-2026-56833 7.5 HIGH PraisonAI Dynamic Context history and terminal tools read files outside configured storage
CVE-2026-56834 7.5 HIGH PraisonAI dynamic-context artifact tools read arbitrary host files outside artifact storag
CVE-2026-57146 7.5 HIGH PraisonAI A2U incomplete authentication fix leaves current serve command unauthenticated b
CVE-2026-57114 7.2 HIGH PraisonAI: Jobs webhook SSRF protection bypass via DNS rebinding

IV. Related Vulnerabilities

Same product: PraisonAI
Same vendor: MervinPraison
Same weakness: CWE-287

V. Comments for CVE-2026-56837

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