Vulnerability · Published Jul 23, 2026 · Assigned by redhat
CVE-2026-6390Nano: gnu nano: arbitrary memory writes, information disclosure, or denial of service via format string vulnerability in error handling.
Medium 6.8
In plain English
A medium-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | nano | no fix listed | DEBIAN-CVE-2026-6390 |
| Debian:13 | nano | no fix listed | DEBIAN-CVE-2026-6390 |
| Debian:14 | nano | 9.0-1 | DEBIAN-CVE-2026-6390 |
| Ubuntu:22.04:LTS | nano | 6.2-1ubuntu0.2 | UBUNTU-CVE-2026-6390 |
| Ubuntu:24.04:LTS | nano | 7.2-2ubuntu0.2 | UBUNTU-CVE-2026-6390 |
| Ubuntu:25.10 | nano | 8.4-1ubuntu0.1 | UBUNTU-CVE-2026-6390 |
| Ubuntu:26.04:LTS | nano | 8.7.1-1ubuntu0.1 | UBUNTU-CVE-2026-6390 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 6 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 5 | see references |
Weakness: CWE-134 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:H
References
- https://access.redhat.com/security/cve/CVE-2026-6390 vdb-entry, x_refsource_REDHAT
- RHBZ#2458767 issue-tracking, x_refsource_REDHAT