Linux Distros Unpatched Vulnerability : CVE-2026-0861

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

include('compat.inc');

if (description)
{
  script_id(286817);
  script_version("1.13");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/16");

  script_cve_id("CVE-2026-0861");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-0861");

  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.

  - Passing too large an alignment to the memalign suite of functions (memalign, posix_memalign,
    aligned_alloc) in the GNU C Library version 2.30 to 2.42 may result in an integer overflow, which could
    consequently result in a heap corruption. Note that the attacker must have control over both, the size as
    well as the alignment arguments of the memalign function to be able to exploit this. The size parameter
    must be close enough to PTRDIFF_MAX so as to overflow size_t along with the large alignment argument. This
    limits the malicious inputs for the alignment for memalign to the range [1<<62+ 1, 1<<63] and exactly
    1<<63 for posix_memalign and aligned_alloc. Typically the alignment argument passed to such functions is a
    known constrained quantity (e.g. page size, block size, struct sizes) and is not attacker controlled,
    because of which this may not be easily exploitable in practice. An application bug could potentially
    result in the input alignment being too large, e.g. due to a different buffer overflow or integer overflow
    in the application or its dependent libraries, but that is again an uncommon usage pattern given typical
    sources of alignments. (CVE-2026-0861)

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-2026-0861");
  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:L/Au:N/C:N/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-0861");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/01/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/01/15");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  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-11");

  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-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "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": "libc0.3-xen"},
          {"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-xen"},
          {"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"}
        ]
      }
    ]
  }
};

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 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');
}