How severe is CVE-2026-39423?

CVE-2026-39423 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-39423 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39423?

CVE-2026-39423 affects Maxkb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39423?

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

Does CVE-2026-39423 have an EU (EUVD) identifier?

Yes. CVE-2026-39423 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22184.

When was CVE-2026-39423 published?

CVE-2026-39423 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-39423

CVE-2026-39423 is a medium-severity vulnerability in Maxkb with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 6.9
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22184
Weakness: CWE-79
Affected product: Maxkb
Published: 2026-04-14
Last modified: 2026-06-17

Description

MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain an Eval Injection vulnerability in the Markdown rendering engine that allows any user capable of interacting with the AI chat interface to execute arbitrary JavaScript in the browsers of other users, including administrators, resulting in Stored Cross-Site Scripting (XSS). This issue has been fixed in version 2.8.0.

Frequently asked questions

What is CVE-2026-39423?: MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain an Eval Injection vulnerability in the Markdown rendering engine that allows any user capable of interacting with the AI chat interface to execute arbitrary JavaScript in the browsers of other users, including administrators, resulting in Stored Cross-Site Scripting (XSS). This issue has been fixed in version 2.8.0.
How severe is CVE-2026-39423?: CVE-2026-39423 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-39423 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39423?: CVE-2026-39423 affects Maxkb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39423?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39423 have an EU (EUVD) identifier?: Yes. CVE-2026-39423 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22184.
When was CVE-2026-39423 published?: CVE-2026-39423 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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