Vulnerability in GNU nano's multi-buffer error message handling (CVE-2026-6390)
Summary
Vulnerability in GNU nano's multi-buffer error message handling (CVE-2026-6390). Data can be tampered with by attackers.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-6390 has been found in GNU nano's multi-buffer error message handling.
Data can be tampered with by attackers. CVSS score: 6.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "GNU nano's multi-buffer error message handling CVE-2026-6390" on the vendor's site.
CVE-2026-6390 (GNU nano's multi-buffer error message handling) — CWE-134 / CVSS v3 6.8
Attack vector: local
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-134) exists in GNU nano's multi-buffer error message handling.
Check the vendor advisory for the affected versions of GNU nano's multi-buffer error message handling.
Severity: Medium (CVSS 6.8/10). Data can be tampered with by attackers.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで GNU nano's multi-buffer error message handling を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-6390 nano
- Debian DEBIAN-CVE-2026-6390 nano
References
- web secalert@redhat.com
- web secalert@redhat.com
- web nvd.nist.gov
- web github.com