Linux Distros Unpatched Vulnerability : CVE-2026-115819

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(379378);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/11/13");

  script_cve_id("CVE-2026-115819");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-115819");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - Calling the wide scanf family of functions (swscanf, fwscanf, wscanf, vswscanf, vfwscanf and vwscanf) with
    a %s or %[ conversion without the 'l' length modifier in the GNU C Library version 2.2 to version 2.44
    writes an extra null byte one past the end of the destination array when the converted multibyte string
    and its terminating null byte exactly fill that array. These conversions store each wide input character
    into the caller's char array as a multibyte sequence. The conversion ends with the sequence that returns
    to the initial shift state, which also stores the terminating null byte, and the functions then append a
    second null byte. A destination sized for the converted string and one terminator, as the C standard
    requires the caller to provide, is therefore written one byte past its end. The out-of-bounds byte is
    always a null byte, which may corrupt adjacent data or crash the process. An attacker who supplies the
    input can trigger the overflow with a string whose converted length exactly fills the destination. The
    narrow scanf functions, the %ls and %l[ conversions into a wchar_t array, and the 'a' and 'm' allocation
    modifiers are not affected, and storing a wide scanf conversion into a narrow char array is uncommon. This
    issue affects all architectures and ABIs supported by the GNU C Library. (CVE-2026-115819)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-115819");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-115819");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/11/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/11/12");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:14.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:glibc");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Debian Linux-12", "Host/OS/Debian Linux-13", "Host/OS/Debian Linux-14");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "glibc-doc"},
          {"reference": "glibc-source"},
          {"reference": "libc-bin"},
          {"reference": "libc-dev-bin"},
          {"reference": "libc-devtools"},
          {"reference": "libc-l10n"},
          {"reference": "libc0.1"},
          {"reference": "libc0.1-dbg"},
          {"reference": "libc0.1-dev"},
          {"reference": "libc0.1-dev-i386"},
          {"reference": "libc0.1-i386"},
          {"reference": "libc0.1-udeb"},
          {"reference": "libc0.3"},
          {"reference": "libc0.3-dbg"},
          {"reference": "libc0.3-dev"},
          {"reference": "libc0.3-udeb"},
          {"reference": "libc6"},
          {"reference": "libc6-amd64"},
          {"reference": "libc6-dbg"},
          {"reference": "libc6-dev"},
          {"reference": "libc6-dev-amd64"},
          {"reference": "libc6-dev-i386"},
          {"reference": "libc6-dev-mips32"},
          {"reference": "libc6-dev-mips64"},
          {"reference": "libc6-dev-mipsn32"},
          {"reference": "libc6-dev-powerpc"},
          {"reference": "libc6-dev-ppc64"},
          {"reference": "libc6-dev-s390"},
          {"reference": "libc6-dev-sparc"},
          {"reference": "libc6-dev-sparc64"},
          {"reference": "libc6-dev-x32"},
          {"reference": "libc6-i386"},
          {"reference": "libc6-mips32"},
          {"reference": "libc6-mips64"},
          {"reference": "libc6-mipsn32"},
          {"reference": "libc6-powerpc"},
          {"reference": "libc6-ppc64"},
          {"reference": "libc6-s390"},
          {"reference": "libc6-sparc"},
          {"reference": "libc6-sparc64"},
          {"reference": "libc6-udeb"},
          {"reference": "libc6-x32"},
          {"reference": "libc6.1"},
          {"reference": "libc6.1-alphaev67"},
          {"reference": "libc6.1-dbg"},
          {"reference": "libc6.1-dev"},
          {"reference": "libc6.1-udeb"},
          {"reference": "locales"},
          {"reference": "locales-all"},
          {"reference": "nscd"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "glibc-doc"},
          {"reference": "glibc-source"},
          {"reference": "libc-bin"},
          {"reference": "libc-dev-bin"},
          {"reference": "libc-devtools"},
          {"reference": "libc-gconv-modules-extra"},
          {"reference": "libc-l10n"},
          {"reference": "libc0.3"},
          {"reference": "libc0.3-dbg"},
          {"reference": "libc0.3-dev"},
          {"reference": "libc0.3-udeb"},
          {"reference": "libc6"},
          {"reference": "libc6-amd64"},
          {"reference": "libc6-dbg"},
          {"reference": "libc6-dev"},
          {"reference": "libc6-dev-amd64"},
          {"reference": "libc6-dev-i386"},
          {"reference": "libc6-dev-mips32"},
          {"reference": "libc6-dev-mips64"},
          {"reference": "libc6-dev-mipsn32"},
          {"reference": "libc6-dev-powerpc"},
          {"reference": "libc6-dev-ppc64"},
          {"reference": "libc6-dev-sparc"},
          {"reference": "libc6-dev-sparc64"},
          {"reference": "libc6-dev-x32"},
          {"reference": "libc6-i386"},
          {"reference": "libc6-mips32"},
          {"reference": "libc6-mips64"},
          {"reference": "libc6-mipsn32"},
          {"reference": "libc6-powerpc"},
          {"reference": "libc6-ppc64"},
          {"reference": "libc6-sparc"},
          {"reference": "libc6-sparc64"},
          {"reference": "libc6-udeb"},
          {"reference": "libc6-x32"},
          {"reference": "libc6.1"},
          {"reference": "libc6.1-dbg"},
          {"reference": "libc6.1-dev"},
          {"reference": "libc6.1-udeb"},
          {"reference": "locales"},
          {"reference": "locales-all"},
          {"reference": "nscd"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "glibc-doc"},
          {"reference": "glibc-source"},
          {"reference": "libc-bin"},
          {"reference": "libc-dev-bin"},
          {"reference": "libc-devtools"},
          {"reference": "libc-l10n"},
          {"reference": "libc0.3"},
          {"reference": "libc0.3-dbg"},
          {"reference": "libc0.3-dev"},
          {"reference": "libc0.3-udeb"},
          {"reference": "libc6"},
          {"reference": "libc6-amd64"},
          {"reference": "libc6-dbg"},
          {"reference": "libc6-dev"},
          {"reference": "libc6-dev-amd64"},
          {"reference": "libc6-dev-i386"},
          {"reference": "libc6-dev-mips32"},
          {"reference": "libc6-dev-mips64"},
          {"reference": "libc6-dev-mipsn32"},
          {"reference": "libc6-dev-powerpc"},
          {"reference": "libc6-dev-ppc64"},
          {"reference": "libc6-dev-s390"},
          {"reference": "libc6-dev-sparc"},
          {"reference": "libc6-dev-sparc64"},
          {"reference": "libc6-dev-x32"},
          {"reference": "libc6-i386"},
          {"reference": "libc6-mips32"},
          {"reference": "libc6-mips64"},
          {"reference": "libc6-mipsn32"},
          {"reference": "libc6-powerpc"},
          {"reference": "libc6-ppc64"},
          {"reference": "libc6-s390"},
          {"reference": "libc6-sparc"},
          {"reference": "libc6-sparc64"},
          {"reference": "libc6-udeb"},
          {"reference": "libc6-x32"},
          {"reference": "libc6.1"},
          {"reference": "libc6.1-dbg"},
          {"reference": "libc6.1-dev"},
          {"reference": "libc6.1-udeb"},
          {"reference": "locales"},
          {"reference": "locales-all"},
          {"reference": "nscd"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}