CVE-2026-6390

Publication date 23 July 2026

Last updated 11 September 2026

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
nano	26.04 LTS resolute	Vulnerable
	24.04 LTS noble	Vulnerable
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Vulnerable
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Vulnerable
	14.04 LTS trusty	Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
nano	Upstream: ?id=0b7

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.8 · Medium

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	Required
Scope	Unchanged
Confidentiality impact	Low
Integrity impact	High
Availability impact	High

Scores

Parameter	Value
Base score	6.8 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:H

References

Other references

https://www.cve.org/CVERecord?id=CVE-2026-6390