Vulnerabilities > CVE-2019-19191 - Link Following vulnerability in Shibboleth Service Provider

047910
CVSS 7.8 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
local
low complexity
shibboleth
CWE-59
nessus
NVD
Published: 2019-11-21
Updated: 2024-11-21

Summary

Shibboleth Service Provider (SP) 3.x before 3.1.0 shipped a spec file that calls chown on files in a directory controlled by the service user (the shibd account) after installation. This allows the user to escalate to root by pointing symlinks to files such as /etc/shadow.

Vulnerable Configurations

Part Description Count
Application
Shibboleth
4

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Symlink Attack
    An attacker positions a symbolic link in such a manner that the targeted user or application accesses the link's endpoint, assuming that it is accessing a file with the link's name. The endpoint file may be either output or input. If the file is output, the result is that the endpoint is modified, instead of a file at the intended location. Modifications to the endpoint file may include appending, overwriting, corrupting, changing permissions, or other modifications. In some variants of this attack the attacker may be able to control the change to a file while in other cases they cannot. The former is especially damaging since the attacker may be able to grant themselves increased privileges or insert false information, but the latter can also be damaging as it can expose sensitive information or corrupt or destroy vital system or application files. Alternatively, the endpoint file may serve as input to the targeted application. This can be used to feed malformed input into the target or to cause the target to process different information, possibly allowing the attacker to control the actions of the target or to cause the target to expose information to the attacker. Moreover, the actions taken on the endpoint file are undertaken with the permissions of the targeted user or application, which may exceed the permissions that the attacker would normally have.
  • Accessing, Modifying or Executing Executable Files
    An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
  • Leverage Executable Code in Non-Executable Files
    An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high. The attack can be directed at a client system, such as causing buffer overrun through loading seemingly benign image files, as in Microsoft Security Bulletin MS04-028 where specially crafted JPEG files could cause a buffer overrun once loaded into the browser. Another example targets clients reading pdf files. In this case the attacker simply appends javascript to the end of a legitimate url for a pdf (http://www.gnucitizen.org/blog/danger-danger-danger/) http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_here The client assumes that they are reading a pdf, but the attacker has modified the resource and loaded executable javascript into the client's browser process. The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality. The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.

Nessus

  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2020-0115-1.NASL
    descriptionThis update for shibboleth-sp fixes the following issues : Security issue fixed : CVE-2019-19191: Fixed escalation to root by fixing ownership of log files (bsc#1157471). Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id133037
    published2020-01-17
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/133037
    titleSUSE SLES12 Security Update : shibboleth-sp (SUSE-SU-2020:0115-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from SUSE update advisory SUSE-SU-2020:0115-1.
# The text itself is copyright (C) SUSE.
#

include("compat.inc");

if (description)
{
  script_id(133037);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/21");

  script_cve_id("CVE-2019-19191");

  script_name(english:"SUSE SLES12 Security Update : shibboleth-sp (SUSE-SU-2020:0115-1)");
  script_summary(english:"Checks rpm output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote SUSE host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"This update for shibboleth-sp fixes the following issues :

Security issue fixed :

CVE-2019-19191: Fixed escalation to root by fixing ownership of log
files (bsc#1157471).

Note that Tenable Network Security has extracted the preceding
description block directly from the SUSE 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://bugzilla.suse.com/show_bug.cgi?id=1157471"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.suse.com/security/cve/CVE-2019-19191/"
  );
  # https://www.suse.com/support/update/announcement/2020/suse-su-20200115-1/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?0a37e56f"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"To install this SUSE Security Update use the SUSE recommended
installation methods like YaST online_update or 'zypper patch'.

Alternatively you can run the command listed for your product :

SUSE OpenStack Cloud Crowbar 8 :

zypper in -t patch SUSE-OpenStack-Cloud-Crowbar-8-2020-115=1

SUSE OpenStack Cloud 8 :

zypper in -t patch SUSE-OpenStack-Cloud-8-2020-115=1

SUSE OpenStack Cloud 7 :

zypper in -t patch SUSE-OpenStack-Cloud-7-2020-115=1

SUSE Linux Enterprise Software Development Kit 12-SP5 :

zypper in -t patch SUSE-SLE-SDK-12-SP5-2020-115=1

SUSE Linux Enterprise Software Development Kit 12-SP4 :

zypper in -t patch SUSE-SLE-SDK-12-SP4-2020-115=1

SUSE Linux Enterprise Server for SAP 12-SP3 :

zypper in -t patch SUSE-SLE-SAP-12-SP3-2020-115=1

SUSE Linux Enterprise Server for SAP 12-SP2 :

zypper in -t patch SUSE-SLE-SAP-12-SP2-2020-115=1

SUSE Linux Enterprise Server for SAP 12-SP1 :

zypper in -t patch SUSE-SLE-SAP-12-SP1-2020-115=1

SUSE Linux Enterprise Server 12-SP5 :

zypper in -t patch SUSE-SLE-SERVER-12-SP5-2020-115=1

SUSE Linux Enterprise Server 12-SP4 :

zypper in -t patch SUSE-SLE-SERVER-12-SP4-2020-115=1

SUSE Linux Enterprise Server 12-SP3-LTSS :

zypper in -t patch SUSE-SLE-SERVER-12-SP3-2020-115=1

SUSE Linux Enterprise Server 12-SP3-BCL :

zypper in -t patch SUSE-SLE-SERVER-12-SP3-BCL-2020-115=1

SUSE Linux Enterprise Server 12-SP2-LTSS :

zypper in -t patch SUSE-SLE-SERVER-12-SP2-2020-115=1

SUSE Linux Enterprise Server 12-SP2-BCL :

zypper in -t patch SUSE-SLE-SERVER-12-SP2-BCL-2020-115=1

SUSE Linux Enterprise Server 12-SP1-LTSS :

zypper in -t patch SUSE-SLE-SERVER-12-SP1-2020-115=1

SUSE Enterprise Storage 5 :

zypper in -t patch SUSE-Storage-5-2020-115=1

HPE Helion Openstack 8 :

zypper in -t patch HPE-Helion-OpenStack-8-2020-115=1"
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  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:suse_linux:libshibsp-lite6");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libshibsp-lite6-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libshibsp6");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:libshibsp6-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:shibboleth-sp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:shibboleth-sp-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:shibboleth-sp-debugsource");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:12");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/11/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/01/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/01/17");
  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:"SuSE Local Security Checks");

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

  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, "SUSE");
os_ver = pregmatch(pattern: "^(SLE(S|D)\d+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "SUSE");
os_ver = os_ver[1];
if (! preg(pattern:"^(SLES12)$", string:os_ver)) audit(AUDIT_OS_NOT, "SUSE SLES12", "SUSE " + os_ver);

if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if (cpu !~ "^i[3-6]86$" && "x86_64" >!< cpu && "s390x" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "SUSE " + os_ver, cpu);

sp = get_kb_item("Host/SuSE/patchlevel");
if (isnull(sp)) sp = "0";
if (os_ver == "SLES12" && (! preg(pattern:"^(1|2|3|4|5)$", string:sp))) audit(AUDIT_OS_NOT, "SLES12 SP1/2/3/4/5", os_ver + " SP" + sp);


flag = 0;
if (rpm_check(release:"SLES12", sp:"1", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"1", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"4", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", cpu:"x86_64", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"3", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", cpu:"x86_64", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"2", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"libshibsp-lite6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"libshibsp-lite6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"libshibsp6-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"libshibsp6-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"shibboleth-sp-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"shibboleth-sp-debuginfo-2.5.5-6.6.1")) flag++;
if (rpm_check(release:"SLES12", sp:"5", reference:"shibboleth-sp-debugsource-2.5.5-6.6.1")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "shibboleth-sp");
}
  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2020-20.NASL
    descriptionThis update for shibboleth-sp fixes the following issues : Security issue fixed : - CVE-2019-19191: Fixed escalation to root by fixing ownership of log files (bsc#1157471). This update was imported from the SUSE:SLE-15:Update update project.
    last seen2020-06-01
    modified2020-06-02
    plugin id132907
    published2020-01-15
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132907
    titleopenSUSE Security Update : shibboleth-sp (openSUSE-2020-20)
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2019-3386-1.NASL
    descriptionThis update for shibboleth-sp fixes the following issues : Security issue fixed : CVE-2019-19191: Fixed escalation to root by fixing ownership of log files (bsc#1157471). Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-01
    modified2020-06-02
    plugin id132396
    published2019-12-24
    reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132396
    titleSUSE SLES15 Security Update : shibboleth-sp (SUSE-SU-2019:3386-1)

References