CVE-2026-39891Public exploitNetwork attack vector

Authenticated command execution via unescaped template expressions

Published Apr 8, 2026 · Updated Apr 8, 2026

Code injection in PraisonAI before 4.5.115 allows remote authenticated users to execute system commands through crafted agent instructions. create_agent_centric_tools() returns tools such as acp_create_file that render unescaped content from agent.start() as template expressions instead of literal text. Exploitation requires access to submit agent instructions to an ACP-enabled runtime using automatic approvals, and commands run with the PraisonAI process privileges.

CVSS severity8.8
High
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in PraisonAI before 4.5.115 allows remote authenticated users to execute system commands through crafted agent instructions. create_agent_centric_tools() returns tools such as acp_create_file that render unescaped content from agent.start() as template expressions instead of literal text. Exploitation requires access to submit agent instructions to an ACP-enabled runtime using automatic approvals, and commands run with the PraisonAI process privileges.

The record

CVE
CVE-2026-39891
Published
Apr 8, 2026
Updated
Apr 8, 2026
Vendor
Mervin Praison
Product
PraisonAI
Classifications
CWE-94, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.5.115

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mervin Praison · PraisonAIversion=< 4.5.115

Published CVSS scores

8.8GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1059Command and Scripting Interpreter

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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