CVE intelligence

CVE-2026-6390

Vulnerability intelligence

Published Jul 23, 2026Sources checked Sep 12, 2026

6.8MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-6390 and is rated Medium severity with a CVSS score of 6.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-6390?

A flaw was found in GNU nano's multi-buffer error message handling. When a user opens multiple files at startup and one triggers an ALERT-level error, a specially crafted filename containing printf format specifiers can be reinterpreted. This format string vulnerability may allow an attacker to achieve stack information disclosure, cause a denial of service (crash), or potentially perform arbitrary memory writes.