nghttp2 security advisories :
The overly large HTTP/2 SETTINGS frame payload causes denial of service.
The proof of concept attack involves a malicious client constructing a SETTINGS frame with a length of 14,400 bytes (2400 individual settings entries) over and over again. The attack causes the CPU to spike at 100%.
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2020 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
# copyright notice, this list of conditions and the following
# disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
# published online in any format, converted to PDF, PostScript,
# RTF and other formats) must reproduce the above copyright
# notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
#
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
include('compat.inc');
if (description)
{
script_id(137126);
script_version("1.4");
script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/05");
script_cve_id("CVE-2020-11080");
script_xref(name:"CEA-ID", value:"CEA-2021-0004");
script_name(english:"FreeBSD : nghttp2 -- DoS vulnerability (4bb56d2f-a5b0-11ea-a860-08002728f74c)");
script_set_attribute(attribute:"synopsis", value:
"The remote FreeBSD host is missing one or more security-related
updates.");
script_set_attribute(attribute:"description", value:
"nghttp2 security advisories :
The overly large HTTP/2 SETTINGS frame payload causes denial of
service.
The proof of concept attack involves a malicious client constructing a
SETTINGS frame with a length of 14,400 bytes (2400 individual settings
entries) over and over again. The attack causes the CPU to spike at
100%.");
# https://github.com/nghttp2/nghttp2/security/advisories/GHSA-q5wr-xfw9-q7xr
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?30f4e11a");
# https://vuxml.freebsd.org/freebsd/4bb56d2f-a5b0-11ea-a860-08002728f74c.html
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?6a1152c9");
script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
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:OF/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:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-11080");
script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
script_set_attribute(attribute:"vuln_publication_date", value:"2020/06/02");
script_set_attribute(attribute:"patch_publication_date", value:"2020/06/03");
script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/04");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:libnghttp2");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:nghttp2");
script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"FreeBSD Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2020-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");
exit(0);
}
include("audit.inc");
include("freebsd_package.inc");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);
flag = 0;
if (pkg_test(save_report:TRUE, pkg:"nghttp2<1.41.0")) flag++;
if (pkg_test(save_report:TRUE, pkg:"libnghttp2<1.41.0")) flag++;
if (flag)
{
if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get());
else security_warning(0);
exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");