Vulnerabilities > CVE-2019-18625

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-2087-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(133363);
  script_version("1.2");
  script_cvs_date("Date: 2020/02/04");

  script_cve_id("CVE-2019-18625", "CVE-2019-18792");

  script_name(english:"Debian DLA-2087-1 : suricata security update");
  script_summary(english:"Checks dpkg output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Two vulnerabilities have recently been discovered in the stream-tcp
code of the intrusion detection and prevention tool Suricata.

CVE-2019-18625

It was possible to bypass/evade any tcp based signature by faking a
closed TCP session using an evil server. After the TCP SYN packet, it
was possible to inject a RST ACK and a FIN ACK packet with a bad TCP
Timestamp option. The client would have ignored the RST ACK and the
FIN ACK packets because of the bad TCP Timestamp option.

CVE-2019-18792

It was possible to bypass/evade any tcp based signature by overlapping
a TCP segment with a fake FIN packet. The fake FIN packet had to be
injected just before the PUSH ACK packet we wanted to bypass. The PUSH
ACK packet (containing the data) would have been ignored by Suricata
because it would have overlapped the FIN packet (the sequence and ack
number are identical in the two packets). The client would have
ignored the fake FIN packet because the ACK flag would not have been
set.

For Debian 8 'Jessie', these problems have been fixed in version
2.0.7-2+deb8u5.

We recommend that you upgrade your suricata packages.

NOTE: Tenable Network Security has extracted the preceding description
block directly from the DLA security advisory. Tenable has attempted
to automatically clean and format it as much as possible without
introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://lists.debian.org/debian-lts-announce/2020/01/msg00032.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/suricata"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Upgrade the affected suricata package."
  );
  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: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:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:suricata");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/01/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/01/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/01/31");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Debian Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("debian_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"8.0", prefix:"suricata", reference:"2.0.7-2+deb8u5")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:deb_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");