Vulnerabilities > CVE-2019-5164 - Missing Authentication for Critical Function vulnerability in multiple products

047910
CVSS 4.6 - MEDIUM
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
local
low complexity
shadowsocks
opensuse
CWE-306
nessus

Summary

An exploitable code execution vulnerability exists in the ss-manager binary of Shadowsocks-libev 3.3.2. Specially crafted network packets sent to ss-manager can cause an arbitrary binary to run, resulting in code execution and privilege escalation. An attacker can send network packets to trigger this vulnerability.

Vulnerable Configurations

Part Description Count
Application
Shadowsocks
1
Application
Opensuse
1
OS
Opensuse
1

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Choosing a Message/Channel Identifier on a Public/Multicast Channel
    Attackers aware that more data is being fed into a multicast or public information distribution means can 'select' information bound only for another client, even if the distribution means itself forces users to authenticate in order to connect initially. Doing so allows the attacker to gain access to possibly privileged information, possibly perpetrate other attacks through the distribution means by impersonation. If the channel/message being manipulated is an input rather than output mechanism for the system, (such as a command bus), this style of attack could change its identifier from a less privileged to more so privileged channel or command.
  • Using Unpublished Web Service APIs
    An attacker searches for and invokes Web Services APIs that the target system designers did not intend to be publicly available. If these APIs fail to authenticate requests the attacker may be able to invoke services and/or gain privileges they are not authorized for.
  • Manipulating Writeable Terminal Devices
    This attack exploits terminal devices that allow themselves to be written to by other users. The attacker sends command strings to the target terminal device hoping that the target user will hit enter and thereby execute the malicious command with their privileges. The attacker can send the results (such as copying /etc/passwd) to a known directory and collect once the attack has succeeded.
  • Cross Site Request Forgery (aka Session Riding)
    An attacker crafts malicious web links and distributes them (via web pages, email, etc.), typically in a targeted manner, hoping to induce users to click on the link and execute the malicious action against some third-party application. If successful, the action embedded in the malicious link will be processed and accepted by the targeted application with the users' privilege level. This type of attack leverages the persistence and implicit trust placed in user session cookies by many web applications today. In such an architecture, once the user authenticates to an application and a session cookie is created on the user's system, all following transactions for that session are authenticated using that cookie including potential actions initiated by an attacker and simply "riding" the existing session cookie.

Nessus

NASL familySuSE Local Security Checks
NASL idOPENSUSE-2019-2667.NASL
descriptionThis update for shadowsocks-libev fixes the following issues : - Update version to 3.3.3 - Refine the handling of suspicious connections. - Fix exploitable denial-of-service vulnerability exists in the UDPRelay functionality (boo#1158251, CVE-2019-5163) - Fix code execution vulnerability in the ss-manager binary (boo#1158365, CVE-2019-5164) - Refine the handling of fragment request. - Fix a high CPU bug introduced in 3.3.0. (#2449) - Enlarge the socket buffer size to 16KB. - Fix the empty list bug in ss-manager. - Fix the IPv6 address parser. - Fix a bug of port parser. - Fix a crash with MinGW. - Refine SIP003 plugin interface. - Remove connection timeout from all clients. - Fix the alignment bug again. - Fix a bug on 32-bit arch. - Add TCP fast open support to ss-tunnel by @PantherJohn.
last seen2020-06-01
modified2020-06-02
plugin id131992
published2019-12-12
reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/131992
titleopenSUSE Security Update : shadowsocks-libev (openSUSE-2019-2667)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from openSUSE Security Update openSUSE-2019-2667.
#
# The text description of this plugin is (C) SUSE LLC.
#

include("compat.inc");

if (description)
{
  script_id(131992);
  script_version("1.2");
  script_cvs_date("Date: 2019/12/16");

  script_cve_id("CVE-2019-5163", "CVE-2019-5164");

  script_name(english:"openSUSE Security Update : shadowsocks-libev (openSUSE-2019-2667)");
  script_summary(english:"Check for the openSUSE-2019-2667 patch");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote openSUSE host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"This update for shadowsocks-libev fixes the following issues :

  - Update version to 3.3.3

  - Refine the handling of suspicious connections.

  - Fix exploitable denial-of-service vulnerability exists
    in the UDPRelay functionality (boo#1158251,
    CVE-2019-5163)

  - Fix code execution vulnerability in the ss-manager
    binary (boo#1158365, CVE-2019-5164)

  - Refine the handling of fragment request.

  - Fix a high CPU bug introduced in 3.3.0. (#2449)

  - Enlarge the socket buffer size to 16KB.

  - Fix the empty list bug in ss-manager.

  - Fix the IPv6 address parser.

  - Fix a bug of port parser.

  - Fix a crash with MinGW.

  - Refine SIP003 plugin interface.

  - Remove connection timeout from all clients.

  - Fix the alignment bug again.

  - Fix a bug on 32-bit arch.

  - Add TCP fast open support to ss-tunnel by @PantherJohn."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1158251"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1158365"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected shadowsocks-libev packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/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:L/AC:L/PR:L/UI:N/S:U/C:H/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:novell:opensuse:libshadowsocks-libev2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:libshadowsocks-libev2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:shadowsocks-libev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:shadowsocks-libev-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:shadowsocks-libev-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:shadowsocks-libev-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:15.1");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/12/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/12/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/12");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"SuSE Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/SuSE/release", "Host/SuSE/rpm-list", "Host/cpu");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/SuSE/release");
if (isnull(release) || release =~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "openSUSE");
if (release !~ "^(SUSE15\.1)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "15.1", release);
if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

ourarch = get_kb_item("Host/cpu");
if (!ourarch) audit(AUDIT_UNKNOWN_ARCH);
if (ourarch !~ "^(x86_64)$") audit(AUDIT_ARCH_NOT, "x86_64", ourarch);

flag = 0;

if ( rpm_check(release:"SUSE15.1", reference:"libshadowsocks-libev2-3.3.3-lp151.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"libshadowsocks-libev2-debuginfo-3.3.3-lp151.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"shadowsocks-libev-3.3.3-lp151.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"shadowsocks-libev-debuginfo-3.3.3-lp151.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"shadowsocks-libev-debugsource-3.3.3-lp151.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.1", reference:"shadowsocks-libev-devel-3.3.3-lp151.2.3.1") ) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libshadowsocks-libev2 / libshadowsocks-libev2-debuginfo / etc");
}

Talos

idTALOS-2019-0958
last seen2019-12-07
published2019-12-03
reporterTalos Intelligence
sourcehttp://www.talosintelligence.com/vulnerability_reports/TALOS-2019-0958
titleShadowsocks-libev ss-manager add_server Code Execution Vulnerability