Linux Distros Unpatched Vulnerability : CVE-2026-73812

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

include('compat.inc');

if (description)
{
  script_id(342611);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/03");

  script_cve_id("CVE-2026-73812");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-73812");

  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.

  - httpd function check_header/3 rejects duplicate Content-Length (per CVE-2026-23941) but never checks for
    the TE+CL co-presence that RFC 9112 6.3 identifies as a probable smuggling attempt. handle_body/3 frames
    by chunked and silently discards Content-Length. A CL-preferring front-end paired with chunked-preferring
    inets creates a classic CL.TE front-end/back-end desync. This issue affects OTP from OTP 17.0 before OTP
    27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to inets
    from 5.10 before 9.3.2.7, from 9.4 before 9.6.2.3, and from 9.7 before 9.7.2. Whether OTP before OTP 17.0,
    corresponding to inets before 5.10, is affected is unknown. (CVE-2026-73812)

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-2026-73812");
  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:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-73812");

  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:"2026/09/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/03");

  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:erlang");
  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": "erlang"},
          {"reference": "erlang-asn1"},
          {"reference": "erlang-base"},
          {"reference": "erlang-common-test"},
          {"reference": "erlang-crypto"},
          {"reference": "erlang-debugger"},
          {"reference": "erlang-dev"},
          {"reference": "erlang-dialyzer"},
          {"reference": "erlang-diameter"},
          {"reference": "erlang-doc"},
          {"reference": "erlang-edoc"},
          {"reference": "erlang-eldap"},
          {"reference": "erlang-erl-docgen"},
          {"reference": "erlang-et"},
          {"reference": "erlang-eunit"},
          {"reference": "erlang-examples"},
          {"reference": "erlang-ftp"},
          {"reference": "erlang-inets"},
          {"reference": "erlang-jinterface"},
          {"reference": "erlang-manpages"},
          {"reference": "erlang-megaco"},
          {"reference": "erlang-mnesia"},
          {"reference": "erlang-mode"},
          {"reference": "erlang-nox"},
          {"reference": "erlang-observer"},
          {"reference": "erlang-odbc"},
          {"reference": "erlang-os-mon"},
          {"reference": "erlang-parsetools"},
          {"reference": "erlang-public-key"},
          {"reference": "erlang-reltool"},
          {"reference": "erlang-runtime-tools"},
          {"reference": "erlang-snmp"},
          {"reference": "erlang-src"},
          {"reference": "erlang-ssh"},
          {"reference": "erlang-ssl"},
          {"reference": "erlang-syntax-tools"},
          {"reference": "erlang-tftp"},
          {"reference": "erlang-tools"},
          {"reference": "erlang-wx"},
          {"reference": "erlang-x11"},
          {"reference": "erlang-xmerl"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "erlang"},
          {"reference": "erlang-asn1"},
          {"reference": "erlang-base"},
          {"reference": "erlang-common-test"},
          {"reference": "erlang-crypto"},
          {"reference": "erlang-debugger"},
          {"reference": "erlang-dev"},
          {"reference": "erlang-dialyzer"},
          {"reference": "erlang-diameter"},
          {"reference": "erlang-doc"},
          {"reference": "erlang-edoc"},
          {"reference": "erlang-eldap"},
          {"reference": "erlang-et"},
          {"reference": "erlang-eunit"},
          {"reference": "erlang-examples"},
          {"reference": "erlang-ftp"},
          {"reference": "erlang-inets"},
          {"reference": "erlang-jinterface"},
          {"reference": "erlang-megaco"},
          {"reference": "erlang-mnesia"},
          {"reference": "erlang-mode"},
          {"reference": "erlang-nox"},
          {"reference": "erlang-observer"},
          {"reference": "erlang-odbc"},
          {"reference": "erlang-os-mon"},
          {"reference": "erlang-parsetools"},
          {"reference": "erlang-public-key"},
          {"reference": "erlang-reltool"},
          {"reference": "erlang-runtime-tools"},
          {"reference": "erlang-snmp"},
          {"reference": "erlang-src"},
          {"reference": "erlang-ssh"},
          {"reference": "erlang-ssl"},
          {"reference": "erlang-syntax-tools"},
          {"reference": "erlang-tftp"},
          {"reference": "erlang-tools"},
          {"reference": "erlang-wx"},
          {"reference": "erlang-x11"},
          {"reference": "erlang-xmerl"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "erlang"},
          {"reference": "erlang-asn1"},
          {"reference": "erlang-base"},
          {"reference": "erlang-common-test"},
          {"reference": "erlang-crypto"},
          {"reference": "erlang-debugger"},
          {"reference": "erlang-dev"},
          {"reference": "erlang-dialyzer"},
          {"reference": "erlang-diameter"},
          {"reference": "erlang-doc"},
          {"reference": "erlang-edoc"},
          {"reference": "erlang-eldap"},
          {"reference": "erlang-et"},
          {"reference": "erlang-eunit"},
          {"reference": "erlang-examples"},
          {"reference": "erlang-ftp"},
          {"reference": "erlang-inets"},
          {"reference": "erlang-jinterface"},
          {"reference": "erlang-megaco"},
          {"reference": "erlang-mnesia"},
          {"reference": "erlang-mode"},
          {"reference": "erlang-nox"},
          {"reference": "erlang-observer"},
          {"reference": "erlang-odbc"},
          {"reference": "erlang-os-mon"},
          {"reference": "erlang-parsetools"},
          {"reference": "erlang-public-key"},
          {"reference": "erlang-reltool"},
          {"reference": "erlang-runtime-tools"},
          {"reference": "erlang-snmp"},
          {"reference": "erlang-src"},
          {"reference": "erlang-ssh"},
          {"reference": "erlang-ssl"},
          {"reference": "erlang-syntax-tools"},
          {"reference": "erlang-tftp"},
          {"reference": "erlang-tools"},
          {"reference": "erlang-wx"},
          {"reference": "erlang-x11"},
          {"reference": "erlang-xmerl"}
        ]
      }
    ]
  }
};

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');
}