CVE-2026-6390: Nano: gnu nano: arbitrary memory writes, information disclosure, or denial of service via format string vulnerability in error handling.
CSIRTS triage
- What
- There is a format string vulnerability in error handling that can lead to arbitrary memory writes, information disclosure, or denial of service.
- Who is affected
- Deployments of gnu nano are affected.
- Urgency
- Remediation is medium urgency due to the potential for exploitation, though it has not been reported as exploited yet.
- Action
- Update to the latest version of gnu nano to mitigate the vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-6390
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-63900.11% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 1% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-6390 | coverage & exploitation status | NVD · CVE.org |
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