Vulnerabilities > CVE-2018-17161 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Freebsd 11.2/12.0

047910
CVSS 7.5 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
network
low complexity
freebsd
CWE-119
nessus

Summary

In FreeBSD before 11.2-STABLE(r348229), 11.2-RELEASE-p7, 12.0-STABLE(r342228), and 12.0-RELEASE-p1, insufficient validation of network-provided data in bootpd may make it possible for a malicious attacker to craft a bootp packet which could cause a stack buffer overflow. It is possible that the buffer overflow could lead to a Denial of Service or remote code execution.

Vulnerable Configurations

Part Description Count
OS
Freebsd
7

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Nessus

NASL familyFreeBSD Local Security Checks
NASL idFREEBSD_SA-18-15_BOOTPD.NASL
descriptionThe version of the FreeBSD kernel running on the remote host is 11.x prior to 11.2-RELEASE-p7 or 12.x prior to 12.0-RELEASE-p1. It is, therefore, affected by a stack buffer overflow vulnerability in bootpd. Insufficient validation of network-provided data in bootpd may make it possible for a malicious attacker to craft a bootp packet which could cause a stack buffer overflow. It is possible that the buffer overflow could lead to a Denial of Service or remote code execution.
last seen2020-03-18
modified2019-07-17
plugin id126754
published2019-07-17
reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/126754
titleFreeBSD 11.x < 11.2-RELEASE-p7 / 12.x < 12.0-RELEASE-p1 bootpd stack buffer overflow
code
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(126754);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/02/21");

  script_cve_id("CVE-2018-17161");
  script_bugtraq_id(106292);

  script_name(english:"FreeBSD 11.x < 11.2-RELEASE-p7 / 12.x < 12.0-RELEASE-p1 bootpd stack buffer overflow");
  script_summary(english:"Checks for the version of the FreeBSD kernel.");

  script_set_attribute(attribute:"synopsis", value:
"The remote FreeBSD host is missing a security-related update.");
  script_set_attribute(attribute:"description", value:
"The version of the FreeBSD kernel running on the remote host is 11.x prior to 11.2-RELEASE-p7 or 12.x prior to
12.0-RELEASE-p1. It is, therefore, affected by a stack buffer overflow vulnerability in bootpd. Insufficient validation
of network-provided data in bootpd may make it possible for a malicious attacker to craft a bootp packet which could
cause a stack buffer overflow. It is possible that the buffer overflow could lead to a Denial of Service or remote code
execution.");
  # https://www.freebsd.org/security/advisories/FreeBSD-SA-18:15.bootpd.asc
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?3ffd9047");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the appropriate FreeBSD version.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-17161");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/12/19");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/12/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/07/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"FreeBSD Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2019-2020 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", "Settings/ParanoidReport");

  exit(0);
}

include("audit.inc");
include("freebsd_package.inc");
include("misc_func.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/FreeBSD/release");
if (!release) audit(AUDIT_OS_NOT, "FreeBSD");

# Patches are available, require paranoid since it is possible
# to manually patch and have a lower OS level.
if (report_paranoia < 2) audit(AUDIT_PARANOID);

fix = NULL;

if (release =~ "^FreeBSD-11\.[0-2]($|[^0-9])")
  fix = "FreeBSD-11.2_7";
else if (release =~ "^FreeBSD-12\.0($|[^0-9])")
  fix = "FreeBSD-12.0_1";

if (isnull(fix) || pkg_cmp(pkg:release, reference:fix) >= 0)
  audit(AUDIT_HOST_NOT, "affected");

report =
  '\n  Installed version : ' + release +
  '\n  Fixed version     : ' + fix +
  '\n';
security_report_v4(port:0, severity:SECURITY_HOLE, extra:report);