How severe is CVE-2026-39424?

CVE-2026-39424 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-39424 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39424?

CVE-2026-39424 affects Maxkb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39424?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39424 have an EU (EUVD) identifier?

Yes. CVE-2026-39424 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22186.

When was CVE-2026-39424 published?

CVE-2026-39424 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-39424

CVE-2026-39424 is a medium-severity vulnerability in Maxkb with a CVSS 3.x base score of 4.7. 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-1236.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
CVSS v4: 5.3
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22186
Weakness: CWE-1236
Affected product: Maxkb
Published: 2026-04-14
Last modified: 2026-06-17

Description

MaxKB is an open-source AI assistant for enterprise. In versions 2.7.1 and below, the chat export feature is vulnerable to Improper Neutralization of Formula Elements in a CSV File. When an administrator exports the application chat history to an Excel file (.xlsx) via the /admin/api/workspace/{workspace_id}/application/{application_id}/chat/export endpoint, strings starting with formula characters are written directly without proper sanitization. Opening this file in spreadsheet applications like Microsoft Excel can lead to Arbitrary Code Execution (RCE) on the administrator's workstation via Dynamic Data Exchange (DDE). The issue is a variant of CVE-2025-4546, which fixed the exact same pattern in apps/dataset/serializers/document_serializers.py but missed the application chat export sink. This issue has been fixed in version 2.8.0.

Frequently asked questions

What is CVE-2026-39424?: MaxKB is an open-source AI assistant for enterprise. In versions 2.7.1 and below, the chat export feature is vulnerable to Improper Neutralization of Formula Elements in a CSV File. When an administrator exports the application chat history to an Excel file (.xlsx) via the /admin/api/workspace/{workspace_id}/application/{application_id}/chat/export endpoint, strings starting with formula characters are written directly without proper sanitization. Opening this file in spreadsheet applications like Microsoft Excel can lead to Arbitrary Code Execution (RCE) on the administrator's workstation via Dynamic Data Exchange (DDE). The issue is a variant of CVE-2025-4546, which fixed the exact same pattern in apps/dataset/serializers/document_serializers.py but missed the application chat export sink. This issue has been fixed in version 2.8.0.
How severe is CVE-2026-39424?: CVE-2026-39424 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-39424 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39424?: CVE-2026-39424 affects Maxkb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39424?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39424 have an EU (EUVD) identifier?: Yes. CVE-2026-39424 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22186.
When was CVE-2026-39424 published?: CVE-2026-39424 was published on 2026-04-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:maxkb:maxkb:*:*:*:*:-:*:*:*

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