---
id: CVE-2026-56837
title: >-
  PraisonAI LinearBot processes unsigned webhooks when LINEAR_WEBHOOK_SECRET is
  missing
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
  onl…
severity: high
cvss: 8.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L'
cvssSource: cna
cwe:
  - CWE-287
  - CWE-306
  - CWE-347
vendor: MervinPraison
product: PraisonAI
affected:
  - 'PraisonAI >= 4.6.56, < 4.6.59'
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-23T17:33:11.010669Z'
published: '2026-10-23'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T21:05:27.023Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-56837'
references:
  - url: >-
      https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-fc26-m9pf-v56q
    label: >-
      https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-fc26-m9pf-v56q
  - url: 'https://github.com/MervinPraison/PraisonAI'
tags:
  - cve.org
  - osv
  - pip
aliases:
  - GHSA-fc26-m9pf-v56q
ecosystem: pip
patched:
  - praisonai 4.6.59
ingestedAt: '2026-07-21T19:04:57.056Z'
epss: 0.00188
epssPercentile: 0.08302
---

## Overview

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.

## Affected

- `PraisonAI >= 4.6.56, < 4.6.59`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-56837)

Affected packages:

- `praisonai >= 4.6.56, < 4.6.59`

Patched in:

- `praisonai 4.6.59`

Source: https://osv.dev/vulnerability/GHSA-fc26-m9pf-v56q