Vulnerabilities > CVE-2018-6556 - Channel and Path Errors vulnerability in multiple products
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
LOW Integrity impact
NONE Availability impact
NONE Summary
lxc-user-nic when asked to delete a network interface will unconditionally open a user provided path. This code path may be used by an unprivileged user to check for the existence of a path which they wouldn't otherwise be able to reach. It may also be used to trigger side effects by causing a (read-only) open of special kernel files (ptmx, proc, sys). Affected releases are LXC: 2.0 versions above and including 2.0.9; 3.0 versions above and including 3.0.0, prior to 3.0.2.
Vulnerable Configurations
Part | Description | Count |
---|---|---|
OS | 1 | |
OS | 2 | |
OS | 1 | |
Application | Linuxcontainers
| 32 |
Application | 3 |
Common Weakness Enumeration (CWE)
Nessus
NASL family SuSE Local Security Checks NASL id OPENSUSE-2019-596.NASL description This update for lxc fixes the following issues : The following security vulnerability was fixed : - CVE-2018-6556: Fixed an information leak and possible open() side effects to regular users via lxc-user-nic (boo#988348) last seen 2020-06-01 modified 2020-06-02 plugin id 123259 published 2019-03-27 reporter This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/123259 title openSUSE Security Update : lxc (openSUSE-2019-596) code # # (C) Tenable Network Security, Inc. # # The descriptive text and package checks in this plugin were # extracted from openSUSE Security Update openSUSE-2019-596. # # The text description of this plugin is (C) SUSE LLC. # include("compat.inc"); if (description) { script_id(123259); script_version("1.2"); script_cvs_date("Date: 2020/01/30"); script_cve_id("CVE-2018-6556"); script_name(english:"openSUSE Security Update : lxc (openSUSE-2019-596)"); script_summary(english:"Check for the openSUSE-2019-596 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 lxc fixes the following issues : The following security vulnerability was fixed : - CVE-2018-6556: Fixed an information leak and possible open() side effects to regular users via lxc-user-nic (boo#988348)" ); script_set_attribute( attribute:"see_also", value:"https://bugzilla.opensuse.org/show_bug.cgi?id=988348" ); script_set_attribute(attribute:"solution", value:"Update the affected lxc packages."); script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N"); 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:L/I:N/A:N"); 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:liblxc-devel"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:liblxc1"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:liblxc1-debuginfo"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:lxc"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:lxc-debuginfo"); script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:lxc-debugsource"); script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:15.0"); script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/10"); script_set_attribute(attribute:"patch_publication_date", value:"2019/03/23"); script_set_attribute(attribute:"plugin_publication_date", value:"2019/03/27"); script_set_attribute(attribute:"generated_plugin", value:"current"); script_end_attributes(); script_category(ACT_GATHER_INFO); script_copyright(english:"This script is Copyright (C) 2019-2020 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/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\.0)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "15.0", release); if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING); ourarch = get_kb_item("Host/cpu"); if (!ourarch) audit(AUDIT_UNKNOWN_ARCH); if (ourarch !~ "^(x86_64)$") audit(AUDIT_ARCH_NOT, "x86_64", ourarch); flag = 0; if ( rpm_check(release:"SUSE15.0", reference:"liblxc-devel-2.0.9-lp150.2.6.1") ) flag++; if ( rpm_check(release:"SUSE15.0", reference:"liblxc1-2.0.9-lp150.2.6.1") ) flag++; if ( rpm_check(release:"SUSE15.0", reference:"liblxc1-debuginfo-2.0.9-lp150.2.6.1") ) flag++; if ( rpm_check(release:"SUSE15.0", reference:"lxc-2.0.9-lp150.2.6.1") ) flag++; if ( rpm_check(release:"SUSE15.0", reference:"lxc-debuginfo-2.0.9-lp150.2.6.1") ) flag++; if ( rpm_check(release:"SUSE15.0", reference:"lxc-debugsource-2.0.9-lp150.2.6.1") ) flag++; if (flag) { if (report_verbosity > 0) security_note(port:0, extra:rpm_report_get()); else security_note(0); exit(0); } else { tested = pkg_tests_get(); if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested); else audit(AUDIT_PACKAGE_NOT_INSTALLED, "liblxc-devel / liblxc1 / liblxc1-debuginfo / lxc / lxc-debuginfo / etc"); }
NASL family SuSE Local Security Checks NASL id OPENSUSE-2018-865.NASL description This update for lxc fixes the following issues : The following security vulnerability was fixed : - CVE-2018-6556: Fixed an information leak and possible open() side effects to regular users via lxc-user-nic (boo#988348) last seen 2020-06-05 modified 2018-08-15 plugin id 111739 published 2018-08-15 reporter This script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/111739 title openSUSE Security Update : lxc (openSUSE-2018-865) NASL family Gentoo Local Security Checks NASL id GENTOO_GLSA-201808-02.NASL description The remote host is affected by the vulnerability described in GLSA-201808-02 (LinuX Containers user space utilities: Arbitrary file read) lxc-user-nic when asked to delete a network interface will unconditionally open a user provided path. This code path may be used by an unprivileged user to check for the existence of a path which they wouldn’t otherwise be able to reach. Impact : A local unprivileged user could use this flaw to access arbitrary files, including special device files. Workaround : There is no known workaround at this time. last seen 2020-06-01 modified 2020-06-02 plugin id 112076 published 2018-08-23 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/112076 title GLSA-201808-02 : LinuX Containers user space utilities: Arbitrary file read NASL family Ubuntu Local Security Checks NASL id UBUNTU_USN-3730-1.NASL description Matthias Gerstner discovered that LXC incorrectly handled the lxc-user-nic utility. A local attacker could possibly use this issue to open arbitrary files. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu 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 111577 published 2018-08-07 reporter Ubuntu Security Notice (C) 2018-2019 Canonical, Inc. / NASL script (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/111577 title Ubuntu 18.04 LTS : lxc vulnerability (USN-3730-1) NASL family SuSE Local Security Checks NASL id OPENSUSE-2019-1275.NASL description This update for lxc, lxcfs to version 3.1.0 fixes the following issues : Security issues fixed : - CVE-2019-5736: Fixed a container breakout vulnerability (boo#1122185). - CVE-2018-6556: Enable setuid bit on lxc-user-nic (boo#988348). Non-security issues fixed : - Update to LXC 3.1.0. The changelog is far too long to include here, please look at https://linuxcontainers.org/. (boo#1131762) last seen 2020-06-01 modified 2020-06-02 plugin id 124312 published 2019-04-26 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/124312 title openSUSE Security Update : lxc / lxcfs (openSUSE-2019-1275) NASL family SuSE Local Security Checks NASL id OPENSUSE-2019-1481.NASL description This update for lxc, lxcfs to version 3.1.0 fixes the following issues : Security issues fixed : - CVE-2019-5736: Fixed a container breakout vulnerability (boo#1122185). - CVE-2018-6556: Enable setuid bit on lxc-user-nic (boo#988348). Non-security issues fixed : - Update to LXC 3.1.0. The changelog is far too long to include here, please look at https://linuxcontainers.org/. (boo#1131762) last seen 2020-06-01 modified 2020-06-02 plugin id 125668 published 2019-06-03 reporter This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/125668 title openSUSE Security Update : lxc / lxcfs (openSUSE-2019-1481)
References
- https://usn.ubuntu.com/usn/usn-3730-1
- https://bugzilla.suse.com/show_bug.cgi?id=988348
- https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1783591
- https://security.gentoo.org/glsa/201808-02
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00074.html
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00076.html
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00091.html
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00073.html