How severe is CVE-2026-39422?

CVE-2026-39422 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-2026-39422 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39422?

CVE-2026-39422 affects Maxkb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39422?

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

Does CVE-2026-39422 have an EU (EUVD) identifier?

Yes. CVE-2026-39422 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22182.

When was CVE-2026-39422 published?

CVE-2026-39422 was published on 2026-04-14 and last updated on 2026-06-17.

CVE-2026-39422

CVE-2026-39422 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% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22182
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 a Stored Cross-Site Scripting (XSS) vulnerability through the application name or icon fields when creating an application. When a victim visits the public chat interface (/ui/chat/{access_token}), the ChatHeadersMiddleware retrieves the application data and directly inserts the unescaped application name and icon into the HTML response via string replacement. This allows an attacker to execute arbitrary JavaScript in the victim's browser context. This issue has been fixed in version 2.8.0.

Frequently asked questions

What is CVE-2026-39422?: MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a Stored Cross-Site Scripting (XSS) vulnerability through the application name or icon fields when creating an application. When a victim visits the public chat interface (/ui/chat/{access_token}), the ChatHeadersMiddleware retrieves the application data and directly inserts the unescaped application name and icon into the HTML response via string replacement. This allows an attacker to execute arbitrary JavaScript in the victim's browser context. This issue has been fixed in version 2.8.0.
How severe is CVE-2026-39422?: CVE-2026-39422 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-2026-39422 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39422?: CVE-2026-39422 affects Maxkb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39422?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39422 have an EU (EUVD) identifier?: Yes. CVE-2026-39422 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22182.
When was CVE-2026-39422 published?: CVE-2026-39422 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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