How severe is CVE-2026-39891?

CVE-2026-39891 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-39891 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39891?

CVE-2026-39891 affects Praison Praisonai. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39891?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-39891 have an EU (EUVD) identifier?

Yes. CVE-2026-39891 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20639.

When was CVE-2026-39891 published?

CVE-2026-39891 was published on 2026-04-08 and last updated on 2026-06-17.

CVE-2026-39891

CVE-2026-39891 is a high-severity vulnerability in Praison Praisonai with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-94.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20639
Weakness: CWE-94
Affected product: Praison Praisonai
Published: 2026-04-08
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-39891?: CVE-2026-39891 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-39891 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39891?: CVE-2026-39891 affects Praison Praisonai. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39891?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-39891 have an EU (EUVD) identifier?: Yes. CVE-2026-39891 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20639.
When was CVE-2026-39891 published?: CVE-2026-39891 was published on 2026-04-08 and last updated on 2026-06-17.

References

https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-hwg5-x759-7wjg

Affected products (1)

cpe:2.3:a:praison:praisonai:*:*:*:*:*:*:*:*

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