HOMEVULNERABILITIESCVE-2026-39423
MEDIUM

CVE-2026-39423

CWE-79Published: April 14, 2026· Updated: Apr 20, 2026

5.4
CVSS v3.1
EPSS:0.04%probability of exploitation in 30 daysPercentile:13.4th

Official 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.

NVD Source

Technical Analysis

CVE-2026-39423 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionRequired
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected Vendors & Products

maxkb1 product
maxkb
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (3)

Quick Facts

CVE IDCVE-2026-39423
CVSS Score5.4 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
EPSS (30d)0.04%
Affected1 vendor
PublishedApr 14, 2026

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-39423 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.