Linux Distros Unpatched Vulnerability : CVE-2026-15711

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

include('compat.inc');

if (description)
{
  script_id(326909);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/16");

  script_cve_id("CVE-2026-15711");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-15711");

  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.

  - A vulnerability was found in libsoup's WebSocket frame parsing implementation. The library fails to
    validate length rules specified in RFC 6455 5.5, which mandates that all WebSocket control frames (e.g.,
    PING, PONG, CLOSE) contain a payload of 125 bytes or less. A remote, unauthenticated attacker can exploit
    this by sending a non-compliant, oversized control frame. Because the parser handles this protocol
    violation improperly instead of throwing an immediate connection termination error, it triggers a internal
    processing crash, resulting in a remote denial of service (DoS) for applications utilizing libsoup
    WebSockets. (CVE-2026-15711)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2026-15711");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-15711");
  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:N/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:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-15711");

  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:"2026/07/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/15");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:8");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:8");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libsoup2.4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libsoup3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libsoup");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libsoup-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libsoup3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libsoup3-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libsoup3-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libsoup");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libsoup-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libsoup3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libsoup3-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:libsoup3-doc");
  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/CentOS Linux-8", "Host/OS/Red Hat Enterprise Linux-10", "Host/OS/Red Hat Enterprise Linux-8", "Host/OS/Red Hat Enterprise Linux-9", "Host/OS/Ubuntu Linux-16.04", "Host/OS/Ubuntu Linux-18.04", "Host/OS/Ubuntu Linux-20.04", "Host/OS/Ubuntu Linux-22.04", "Host/OS/Ubuntu Linux-24.04", "Host/OS/Ubuntu Linux-26.04");

  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/CentOS/rpm-list")) && empty_or_null(get_one_kb_item("Host/Debian/dpkg-l")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "gir1.2-soup-2.4"},
          {"reference": "libsoup-gnome2.4-1"},
          {"reference": "libsoup-gnome2.4-dev"},
          {"reference": "libsoup2.4-1"},
          {"reference": "libsoup2.4-dbg"},
          {"reference": "libsoup2.4-dev"},
          {"reference": "libsoup2.4-doc"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "gir1.2-soup-2.4"},
          {"reference": "libsoup-gnome2.4-1"},
          {"reference": "libsoup-gnome2.4-dev"},
          {"reference": "libsoup2.4-1"},
          {"reference": "libsoup2.4-dev"},
          {"reference": "libsoup2.4-doc"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "gir1.2-soup-2.4"},
          {"reference": "libsoup-gnome2.4-1"},
          {"reference": "libsoup-gnome2.4-dev"},
          {"reference": "libsoup2.4-1"},
          {"reference": "libsoup2.4-dev"},
          {"reference": "libsoup2.4-doc"},
          {"reference": "libsoup2.4-tests"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "gir1.2-soup-2.4"},
          {"reference": "libsoup-gnome2.4-1"},
          {"reference": "libsoup-gnome2.4-dev"},
          {"reference": "libsoup2.4-1"},
          {"reference": "libsoup2.4-common"},
          {"reference": "libsoup2.4-dev"},
          {"reference": "libsoup2.4-doc"},
          {"reference": "libsoup2.4-tests"},
          {"reference": "libsoup3"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "gir1.2-soup-2.4"},
          {"reference": "gir1.2-soup-3.0"},
          {"reference": "libsoup-2.4-1"},
          {"reference": "libsoup-3.0-0"},
          {"reference": "libsoup-3.0-common"},
          {"reference": "libsoup-3.0-dev"},
          {"reference": "libsoup-3.0-doc"},
          {"reference": "libsoup-3.0-tests"},
          {"reference": "libsoup-gnome-2.4-1"},
          {"reference": "libsoup-gnome2.4-dev"},
          {"reference": "libsoup2.4-common"},
          {"reference": "libsoup2.4-dev"},
          {"reference": "libsoup2.4-doc"},
          {"reference": "libsoup2.4-tests"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "gir1.2-soup-3.0"},
          {"reference": "libsoup-3.0-0"},
          {"reference": "libsoup-3.0-common"},
          {"reference": "libsoup-3.0-dev"},
          {"reference": "libsoup-3.0-doc"},
          {"reference": "libsoup-3.0-tests"},
          {"reference": "libsoup2.4"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "libsoup3"},
          {"reference": "libsoup3-devel"},
          {"reference": "libsoup3-doc"}
        ]
      }
    ]
  },
  "CentOS Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "libsoup"},
          {"reference": "libsoup-devel"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "libsoup"},
          {"reference": "libsoup-devel"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "libsoup"},
          {"reference": "libsoup-devel"}
        ]
      }
    ]
  }
};

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');
}