Bug 2460017 (CVE-2026-6843)

Summary: CVE-2026-6843 nano: nano: Format string vulnerability leads to Denial of Service
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in nano. A local user could exploit a format string vulnerability in the `statusline()` function. By creating a directory with a name containing `printf` specifiers, the application attempts to display this name, leading to a segmentation fault (SEGV). This results in a Denial of Service (DoS) for the `nano` application.
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Bug Depends On: 2460503    
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Description OSIDB Bzimport 2026-04-21 08:47:01 UTC 
Format string vulnerability in nano's statusline(). Directory names containing printf specifiers (%s) are stored in errormessage and later passed as format string to statusline() with no args. Causes stack reads and SEGV.

Verified on nano 8.7 with ASAN. BZ#2455127.
Reported by Michał Majchrowicz and Marcin Wyczechowski, AFINE Team.