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.

An update of the nano package has been released.

The remote openSUSE 16 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:21166-1 advisory.

    Changes in nano:

    - Update to version 9.1:
      * When searching, the viewport is placed snug left where         possible.
      * The ability to read and write files in old Mac format (a lone         carriage return as line ending) was removed.
      * The ^T toggle between WhereIs and GotoLine was dropped.
      * Fix backups that were missing or had a wrong timestamp when
        --backup is active.
      * On a crash or kill, a .save file is no longer chmodded or         chowned to the base file's permissions and owner.
      * The history code now creates the ~/.local directory with         limited access rights (boo#1263437; the referenced         CVE-2026-40556 was rejected upstream).
      * M-Ins and M-Del have become rebindable.

    - GNU nano 9.0:
      * When the cursor almost goes offscreen to the right, all lines         are now scrolled sideways together, by just the amount needed         to keep the cursor in view.
        Use --solosidescroll or 'set solosidescroll' to get back the         old, jerky, single-line horizontal scrolling.
      * The viewport can be scrolled sideways (in steps of one         tabsize) with M-< and M->.  See `man nanorc` if M-< and M->         should switch between buffers (as they did earlier).
      * M-Left, M-Right, M-Up, and M-Down have become rebindable.
      * Stopping the recording of a macro immediately after starting         it cancels the recording and leaves an existing macro in place.
      * Feature toggles no longer break a chain of ^K cuts or M-6         copies, except the M-K cut-from-cursor toggle.
      * With --mouse and --indicator, one can click in the scrollbar         area to roughly navigate within the buffer.
      * CVE-2026-6843: format string vulnerability leads to denial of         service (boo#1262643)
      * create the ~/.local directory with limited access rights         (CVE-2026-6842 boo#1263022, CVE-2026-40556 boo#1263437)

    - GNU nano 8.7.1:
      * fix build against glibc-2.43 (boo#1258260)

    - GNU nano 8.7:
      * At the Execute prompt, preceding the command with two pipe         symbols allows implementing a copy-to-clipboard feature in         nanorc on terminals that support OSC 52. See doc/sample.nanorc

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8386-1 advisory.

    Micha Majchrowicz and Marcin Wyczechowski discovered that Nano created the ~/.local directory with     incorrect permissions. In environments with permissive umask settings, a local attacker could possibly use     this issue to inject a malicious launcher file, resulting in information disclosure or other unintended     actions. (CVE-2026-6842)

    Micha Majchrowicz and Marcin Wyczechowski discovered that Nano incorrectly handled directory names when     updating the status line. A local attacker could possibly use this issue to cause Nano to crash, resulting     in a denial of service. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10, and     Ubuntu 26.04 LTS. (CVE-2026-6843)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 42 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-fbeaecb457 advisory.

    * fix CVE-2026-6842 and CVE-29026-6843

    Resolves: CVE-2026-6842     Resolves: CVE-2026-6843     Resolves: rhbz#2455127     Resolves: rhbz#2455314


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-d0a0f1c3d2 advisory.

    * fix CVE-2026-6842 and CVE-29026-6843

    Resolves: CVE-2026-6842     Resolves: CVE-2026-6843     Resolves: rhbz#2455127     Resolves: rhbz#2455314


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-3111ffa11a advisory.

    * fix CVE-2026-6842 and CVE-29026-6843

    Resolves: CVE-2026-6842     Resolves: CVE-2026-6843     Resolves: rhbz#2455127     Resolves: rhbz#2455314


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-6843)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
332728	Photon OS 5.0: Nano PHSA-2026-5.0-91-0886	Nessus	PhotonOS Local Security Checks	Local	medium
324062	openSUSE 16 Security Update : nano (openSUSE-SU-2026:21166-1)	Nessus	SuSE Local Security Checks	Local	low
321791	Photon OS 5.0: Nano PHSA-2026-5.0-0886	Nessus	PhotonOS Local Security Checks	Local	medium
318839	Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : Nano vulnerabilities (USN-8386-1)	Nessus	Ubuntu Local Security Checks	Local	low
314524	Fedora 42 : nano (2026-fbeaecb457)	Nessus	Fedora Local Security Checks	Local	low
313026	Fedora 43 : nano (2026-d0a0f1c3d2)	Nessus	Fedora Local Security Checks	Local	low
312244	Fedora 44 : nano (2026-3111ffa11a)	Nessus	Fedora Local Security Checks	Local	low
309201	Linux Distros Unpatched Vulnerability : CVE-2026-6843	Nessus	Misc.	Local	medium

Detections

Analytics

CVE-2026-6843

medium

Tenable Plugins

medium

low

medium

low

low

low

low

medium