Vulnerabilities > CVE-2017-7995 - Information Exposure vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
LOW Integrity impact
NONE Availability impact
NONE Summary
Xen PV guest before Xen 4.3 checked access permissions to MMIO ranges only after accessing them, allowing host PCI device space memory reads, leading to information disclosure. This is an error in the get_user function. NOTE: the upstream Xen Project considers versions before 4.5.x to be EOL.
Vulnerable Configurations
Part | Description | Count |
---|---|---|
OS | Xen
| 85 |
OS | 2 | |
Application | 3 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Subverting Environment Variable Values The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
- Footprinting An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
- Exploiting Trust in Client (aka Make the Client Invisible) An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
- Browser Fingerprinting An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
- Session Credential Falsification through Prediction This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.
Nessus
NASL family SuSE Local Security Checks NASL id SUSE_SU-2017-1146-1.NASL description This update for xen fixes several security issues : - A malicious 64-bit PV guest may be able to access all of system memory, allowing for all of privilege escalation, host crashes, and information leaks by placing a IRET hypercall in the middle of a multicall batch (XSA-213, bsc#1034843) - A malicious pair of guests may be able to access all of system memory, allowing for all of privilege escalation, host crashes, and information leaks because of a missing check when transfering pages via GNTTABOP_transfer (XSA-214, bsc#1034844). - CVE-2017-7718: hw/display/cirrus_vga_rop.h allowed local guest OS privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) via vectors related to copying VGA data via the cirrus_bitblt_rop_fwd_transp_ and cirrus_bitblt_rop_fwd_ functions (bsc#1034994). - CVE-2016-9603: A privileged user within the guest VM could have caused a heap overflow in the device model process, potentially escalating their privileges to that of the device model process (bsc#1028655) 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 seen 2020-06-01 modified 2020-06-02 plugin id 99961 published 2017-05-03 reporter This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/99961 title SUSE SLES11 Security Update : xen (SUSE-SU-2017:1146-1) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from SUSE update advisory SUSE-SU-2017:1146-1. # The text itself is copyright (C) SUSE. # include("compat.inc"); if (description) { script_id(99961); script_version("3.13"); script_cvs_date("Date: 2019/09/11 11:22:15"); script_cve_id("CVE-2016-9603", "CVE-2017-7718", "CVE-2017-7980", "CVE-2017-7995"); script_name(english:"SUSE SLES11 Security Update : xen (SUSE-SU-2017:1146-1)"); 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 xen fixes several security issues : - A malicious 64-bit PV guest may be able to access all of system memory, allowing for all of privilege escalation, host crashes, and information leaks by placing a IRET hypercall in the middle of a multicall batch (XSA-213, bsc#1034843) - A malicious pair of guests may be able to access all of system memory, allowing for all of privilege escalation, host crashes, and information leaks because of a missing check when transfering pages via GNTTABOP_transfer (XSA-214, bsc#1034844). - CVE-2017-7718: hw/display/cirrus_vga_rop.h allowed local guest OS privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) via vectors related to copying VGA data via the cirrus_bitblt_rop_fwd_transp_ and cirrus_bitblt_rop_fwd_ functions (bsc#1034994). - CVE-2016-9603: A privileged user within the guest VM could have caused a heap overflow in the device model process, potentially escalating their privileges to that of the device model process (bsc#1028655) 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=1028655" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1033948" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1034843" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1034844" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1034845" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1034994" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.suse.com/show_bug.cgi?id=1035483" ); script_set_attribute( attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2016-9603/" ); script_set_attribute( attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2017-7718/" ); script_set_attribute( attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2017-7980/" ); script_set_attribute( attribute:"see_also", value:"https://www.suse.com/security/cve/CVE-2017-7995/" ); # https://www.suse.com/support/update/announcement/2017/suse-su-20171146-1/ script_set_attribute( attribute:"see_also", value:"http://www.nessus.org/u?f504077b" ); script_set_attribute( attribute:"solution", value: "To install this SUSE Security Update use YaST online_update. Alternatively you can run the command listed for your product : SUSE OpenStack Cloud 5:zypper in -t patch sleclo50sp3-xen-13085=1 SUSE Manager Proxy 2.1:zypper in -t patch slemap21-xen-13085=1 SUSE Manager 2.1:zypper in -t patch sleman21-xen-13085=1 SUSE Linux Enterprise Server 11-SP3-LTSS:zypper in -t patch slessp3-xen-13085=1 SUSE Linux Enterprise Point of Sale 11-SP3:zypper in -t patch sleposp3-xen-13085=1 To bring your system up-to-date, use 'zypper patch'." ); script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/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:N/AC:L/PR:L/UI:N/S:C/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:"exploit_available", value:"false"); script_set_attribute(attribute:"plugin_type", value:"local"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-doc-html"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-doc-pdf"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-kmp-default"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-kmp-pae"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-libs"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-tools"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:suse_linux:xen-tools-domU"); script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:suse_linux:11"); script_set_attribute(attribute:"vuln_publication_date", value:"2017/04/20"); script_set_attribute(attribute:"patch_publication_date", value:"2017/05/02"); script_set_attribute(attribute:"plugin_publication_date", value:"2017/05/03"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2017-2019 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/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:"^(SLES11)$", string:os_ver)) audit(AUDIT_OS_NOT, "SUSE SLES11", "SUSE " + os_ver); if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); cpu = get_kb_item("Host/cpu"); if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH); if (cpu !~ "^i[3-6]86$" && "x86_64" >!< cpu && "s390x" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "SUSE " + os_ver, cpu); if (cpu >!< "i386|i486|i586|i686|x86_64") audit(AUDIT_ARCH_NOT, "i386 / i486 / i586 / i686 / x86_64", cpu); sp = get_kb_item("Host/SuSE/patchlevel"); if (isnull(sp)) sp = "0"; if (os_ver == "SLES11" && (! preg(pattern:"^(3)$", string:sp))) audit(AUDIT_OS_NOT, "SLES11 SP3", os_ver + " SP" + sp); flag = 0; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-kmp-default-4.2.5_21_3.0.101_0.47.99-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-libs-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-tools-domU-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-doc-html-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-doc-pdf-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-libs-32bit-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-tools-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"x86_64", reference:"xen-kmp-pae-4.2.5_21_3.0.101_0.47.99-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"i586", reference:"xen-kmp-default-4.2.5_21_3.0.101_0.47.99-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"i586", reference:"xen-libs-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"i586", reference:"xen-tools-domU-4.2.5_21-41.1")) flag++; if (rpm_check(release:"SLES11", sp:"3", cpu:"i586", reference:"xen-kmp-pae-4.2.5_21_3.0.101_0.47.99-41.1")) 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, "xen"); }
NASL family Debian Local Security Checks NASL id DEBIAN_DLA-964.NASL description Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems : CVE-2016-9932 (XSA-200) CMPXCHG8B emulation allows local HVM guest OS users to obtain sensitive information from host stack memory. CVE-2017-7995 Description Xen checks access permissions to MMIO ranges only after accessing them, allowing host PCI device space memory reads. CVE-2017-8903 (XSA-213) Xen mishandles page tables after an IRET hypercall which can lead to arbitrary code execution on the host OS. The vulnerability is only exposed to 64-bit PV guests. CVE-2017-8904 (XSA-214) Xen mishandles the last seen 2020-03-17 modified 2017-06-02 plugin id 100575 published 2017-06-02 reporter This script is Copyright (C) 2017-2020 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/100575 title Debian DLA-964-1 : xen security update
References
- http://lists.opensuse.org/opensuse-security-announce/2017-05/msg00005.html
- http://lists.opensuse.org/opensuse-security-announce/2017-05/msg00005.html
- http://www.securityfocus.com/bid/98314
- http://www.securityfocus.com/bid/98314
- https://bugzilla.suse.com/show_bug.cgi?id=1033948
- https://bugzilla.suse.com/show_bug.cgi?id=1033948