CVE-2026-86098 and is rated High severity with a CVSS score of 7.4. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
What to do next
Remediation and response
Microsoft Security Response Center guidance
Vendor revision: Oct 23, 2026
Release Notes
Vendor-listed releases
5.2.1-7
CISA KEVNot listedBased on the latest collected catalog
EPSS0.6%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-86098?
ntop nDPI versions before 6.0 contain a heap buffer overflow vulnerability in the ndpi_json_string_escape function that writes beyond caller-supplied buffer boundaries. Attackers can trigger the overflow by supplying crafted network packet data including TLS SNI, HTTP headers, or DNS names that reach the vulnerable function, causing heap corruption.