TI-2026-79614 Aliases CVE-2026-56837

PraisonAI LinearBot accepts unsigned webhooks when secret is unset

MEDIUM 42CWE-287Published 2026-10-23 · Updated 2026-10-23

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: Low · High · Low
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-287.

Summary

PraisonAI from 4.6.56 before 4.6.59 starts a public LinearBot webhook listener that skips Linear-Signature verification when LINEAR_WEBHOOK_SECRET is not set (CWE-347). An unauthenticated remote attacker who can reach the webhook endpoint can submit forged agent session requests, which the bot processes and answers using its configured Linear bot token.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00188 8th percentileScored 2026-11-07

Fix Fixed PraisonAI (MervinPraison): 4.6.59praisonai (PyPI): 4.6.59

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
MervinPraison	PraisonAI	4.6.56 to before 4.6.59	4.6.59	Patch available	CNA
—	praisonai (PyPI)	4.6.56 to before 4.6.59	4.6.59	Patch available	GHSA-fc26-m9pf-v56q

PraisonAI VendorMervinPraison Affected 4.6.56 to before 4.6.59 Fixed in 4.6.59 Patch available CNA
praisonai (PyPI) Vendor— Affected 4.6.56 to before 4.6.59 Fixed in 4.6.59 Patch available GHSA-fc26-m9pf-v56q

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:praison:praisonai::::::::	—	—	MervinPraison

cpe:2.3:a:praison:praisonai:*:*:*:*:*:*:*:* Versions — — ·MervinPraison

Remediation

Upgrade the PyPI package praisonai to version 4.6.59, which fixes the issue. The sources list no fixed version for PraisonAI.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Fix · CNA PraisonAI (MervinPraison) Fixed in 4.6.59
Fix · GHSA-fc26-m9pf-v56q praisonai (PyPI) Fixed in 4.6.59 Advisory →

Timeline

2026-10-23 Threatist record created from CVE-2026-56837
2026-10-23 CISA SSVC decision points changed

References

Other 2

TI-2026-79619 Missing authentication in PraisonAI AgentOS exposes agent chat CVSS 3.1CRITICAL 9.8
TI-2026-71236 Missing access control in PraisonAI AgentTeam exposes agent endpoints CVSS 3.1CRITICAL 9.8
TI-2026-44052 PraisonAI before 1.6.78 Remote Code Execution via CodeAgent CVSS 4.0CRITICAL 10.0
TI-2026-41123 praisonai-platform 0.1.4 still boots on the hardcoded JWT secret dev-secret-change-me (default-open production guard) CVSS 3.1CRITICAL 9.8
TI-2026-41122 praisonai-platform: default JWT signing secret 'dev-secret-change-me' enables token forgery CVSS 3.1CRITICAL 9.8
TI-2026-41118 PraisonAI MCPServer exposes unauthenticated HTTP tools/call CVSS 3.1CRITICAL 9.8

See all 177 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences