What is CVE-2026-39891?

CVE-2026-39891 is a high-severity vulnerability in Mervinpraison Praisonai, classified under Code Injection. CVSS score: 8.8/10. Published 2026-04-08.

How severe is CVE-2026-39891?

High severity. CVSS v3 base score is 8.8 out of 10.

RCE in Mervinpraison Praisonai

CVE-2026-39891

PraisonAI is a multi-agent teams system. Prior to 4.5.115, the create_agent_centric_tools() function returns tools (like acp_create_file) that process file content using template rendering. When user input from agent.start() is passed directly into these tools without escaping, template expressions in the input are executed rather than treated as literal text. This vulnerability is fixed in 4.5.115.

Vulnerability class: RCE (Remote Code Execution)

Published 2026-04-08 · last modified 2026-07-24.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (44.4th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000

Affected products

Mervinpraison Praisonai — versions < 4.5.115
Praison Praisonai

Weakness classification (CWE)

CWE-94 — Code Injection

References

github.com/MervinPraison/PraisonAI/security/advisories/GHSA-hwg5-x759-7wjg (Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2026-39891?: CVE-2026-39891 is a high-severity vulnerability in Mervinpraison Praisonai, classified under Code Injection. CVSS score: 8.8/10. Published 2026-04-08.
How severe is CVE-2026-39891?: High severity. CVSS v3 base score is 8.8 out of 10.