An issue was discovered in the Linux kernel before 4.8. Incorrect access checking in overlayfs mounts could be used by local attackers to modify or truncate files in the underlying filesystem.

New kernel packages are available for Slackware 14.2 to fix security issues.

An update of the linux package has been released.

According to the versions of the kernel packages installed, the EulerOS Virtualization for ARM 64 installation on the remote host is affected by the following vulnerabilities :

  - Linux kernel built with the KVM visualization support     (CONFIG_KVM), with nested visualization(nVMX) feature     enabled(nested=1), is vulnerable to host memory leakage     issue. It could occur while emulating VMXON instruction     in 'handle_vmon'. An L1 guest user could use this flaw     to leak host memory potentially resulting in     DoS.(CVE-2017-2596i1/4%0

  - The (1) BPF_S_ANC_NLATTR and (2) BPF_S_ANC_NLATTR_NEST     extension implementations in the sk_run_filter function     in net/core/filter.c in the Linux kernel through 3.14.3     do not check whether a certain length value is     sufficiently large, which allows local users to cause a     denial of service (integer underflow and system crash)     via crafted BPF instructions. NOTE: the affected code     was moved to the __skb_get_nlattr and
    __skb_get_nlattr_nest functions before the     vulnerability was announced.(CVE-2014-3144i1/4%0

  - A flaw was found in the Linux kernel when freeing pages     in hugetlbfs. This could trigger a local denial of     service by crashing the kernel.(CVE-2017-15127i1/4%0

  - An issue was discovered in the Linux kernel before 4.8.
    Incorrect access checking in overlayfs mounts could be     used by local attackers to modify or truncate files in     the underlying filesystem.(CVE-2018-16597i1/4%0

  - Memory leak in the cuse_channel_release function in     fs/fuse/cuse.c in the Linux kernel before 4.4 allows     local users to cause a denial of service (memory     consumption) or possibly have unspecified other impact     by opening /dev/cuse many times.(CVE-2015-1339i1/4%0

  - A flaw was found in the way the Linux kernel's nested     NMI handler and espfix64 functionalities interacted     during NMI processing. A local, unprivileged user could     use this flaw to crash the system or, potentially,     escalate their privileges on the     system.(CVE-2015-3290i1/4%0

  - Multiple array index errors in     drivers/hid/hid-multitouch.c in the Human Interface     Device (HID) subsystem in the Linux kernel through     3.11, when CONFIG_HID_MULTITOUCH is enabled, allow     physically proximate attackers to cause a denial of     service (heap memory corruption, or NULL pointer     dereference and OOPS) via a crafted     device.(CVE-2013-2897i1/4%0

  - A flaw was found in the way the Linux kernel's futex     subsystem handled the requeuing of certain Priority     Inheritance (PI) futexes. A local, unprivileged user     could use this flaw to escalate their privileges on the     system.(CVE-2014-3153i1/4%0

  - The XFS subsystem in the Linux kernel 4.4 and later     allows local users to cause a denial of service     (fdatasync() failure and system hang) by using the vfs     syscall group in the 'trinity' program, as a result of     a page lock order bug in the XFS seek hole/data     implementation.(CVE-2016-8660i1/4%0

  - A flaw was found in the Linux kernel's key management     system where it was possible for an attacker to     escalate privileges or crash the machine. If a user key     gets negatively instantiated, an error code is cached     in the payload area. A negatively instantiated key may     be then be positively instantiated by updating it with     valid data. However, the -i1/4zupdate key type method     must be aware that the error code may be     there.(CVE-2015-8539i1/4%0

  - It was found that the Linux kernel KVM subsystem's     sysenter instruction emulation was not sufficient. An     unprivileged guest user could use this flaw to escalate     their privileges by tricking the hypervisor to emulate     a SYSENTER instruction in 16-bit mode, if the guest OS     did not initialize the SYSENTER model-specific     registers (MSRs). Note: Certified guest operating     systems for Red Hat Enterprise Linux with KVM do     initialize the SYSENTER MSRs and are thus not     vulnerable to this issue when running on a KVM     hypervisor.(CVE-2015-0239i1/4%0

  - An information leak flaw was found in the way the Linux     kernel handled media device enumerate entities IOCTL     requests. A local user able to access the /dev/media0     device file could use this flaw to leak kernel memory     bytes.(CVE-2014-1739i1/4%0

  - The dgnc_mgmt_ioctl function in     drivers/staging/dgnc/dgnc_mgmt.c in the Linux kernel     through 4.3.3 does not initialize a certain structure     member, which allows local users to obtain sensitive     information from kernel memory via a crafted     application.(CVE-2015-7885i1/4%0

  - An information leak was discovered in the Linux kernel     in cdrom_ioctl_drive_status() function in     drivers/cdrom/cdrom.c that could be used by local     attackers to read kernel memory at certain     location.(CVE-2018-16658i1/4%0

  - A flaw was discovered in the Linux kernel's     implementation of VFIO. An attacker issuing an ioctl     can create a situation where memory is corrupted and     modify memory outside of the expected area. This may     overwrite kernel memory and subvert kernel     execution.(CVE-2016-9083i1/4%0

  - It was found that the Linux kernel's KVM subsystem did     not handle the VM exits gracefully for the invvpid     (Invalidate Translations Based on VPID) instructions.
    On hosts with an Intel processor and invppid VM exit     support, an unprivileged guest user could use these     instructions to crash the guest.(CVE-2014-3646i1/4%0

  - An attacker on a network could abuse a flaw in the IPv6     stack fragment reassembly code to induce kernel memory     corruption on the system, possibly leading to a system     crash.(CVE-2016-9755i1/4%0

  - It was found that a regular user could remove xattr     permissions on files by using the chown or write system     calls. A local attacker could use this flaw to deny     elevated permissions from valid users, services, or     applications, potentially resulting in a denial of     service.(CVE-2015-1350i1/4%0

  - arch/powerpc/kvm/book3s_hv_rmhandlers.S in the Linux     kernel through 4.7 on PowerPC platforms, when     CONFIG_KVM_BOOK3S_64_HV is enabled, allows guest OS     users to cause a denial of service (host OS infinite     loop) by making a H_CEDE hypercall during the existence     of a suspended transaction.(CVE-2016-5412i1/4%0

  - An issue was discovered in the proc_pid_stack function     in fs/proc/base.c in the Linux kernel. An attacker with     a local account can trick the stack unwinder code to     leak stack contents to userspace. The fix allows only     root to inspect the kernel stack of an arbitrary     task.(CVE-2018-17972i1/4%0

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The SUSE Linux Enterprise 12 SP3 Azure kernel was updated to 4.4.162 to receive various security and bugfixes.

The following security bugs were fixed :

CVE-2018-18281: The mremap() syscall performs TLB flushes after dropping pagetable locks. If a syscall such as ftruncate() removes entries from the pagetables of a task that is in the middle of mremap(), a stale TLB entry can remain for a short time that permits access to a physical page after it has been released back to the page allocator and reused. (bnc#1113769).

CVE-2018-18710: An information leak in cdrom_ioctl_select_disc in drivers/cdrom/cdrom.c could be used by local attackers to read kernel memory because a cast from unsigned long to int interferes with bounds checking. This is similar to CVE-2018-10940 and CVE-2018-16658 (bnc#1113751).

CVE-2018-18690: A local attacker able to set attributes on an xfs filesystem could make this filesystem non-operational until the next mount by triggering an unchecked error condition during an xfs attribute change, because xfs_attr_shortform_addname in fs/xfs/libxfs/xfs_attr.c mishandled ATTR_REPLACE operations with conversion of an attr from short to long form (bnc#1105025).

CVE-2018-18386: drivers/tty/n_tty.c allowed local attackers (who are able to access pseudo terminals) to hang/block further usage of any pseudo terminal devices due to an EXTPROC versus ICANON confusion in TIOCINQ (bnc#1094825).

CVE-2018-9516: In hid_debug_events_read of drivers/hid/hid-debug.c, there is a possible out of bounds write due to a missing bounds check.
This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
(bnc#1108498).

CVE-2018-14633: A security flaw was found in the chap_server_compute_md5() function in the ISCSI target code in a way an authentication request from an ISCSI initiator is processed. An unauthenticated remote attacker can cause a stack-based buffer overflow and smash up to 17 bytes of the stack. The attack requires the iSCSI target to be enabled on the victim host. Depending on how the target's code was built (i.e. depending on a compiler, compile flags and hardware architecture) an attack may lead to a system crash and thus to a denial-of-service or possibly to a non-authorized access to data exported by an iSCSI target. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is highly unlikely. (bnc#1107829).

CVE-2018-17182: The vmacache_flush_all function in mm/vmacache.c mishandled sequence number overflows. An attacker can trigger a use-after-free (and possibly gain privileges) via certain thread creation, map, unmap, invalidation, and dereference operations (bnc#1108399).

CVE-2018-16597: Incorrect access checking in overlayfs mounts could be used by local attackers to modify or truncate files in the underlying filesystem (bnc#1106512).

CVE-2018-14613: There is an invalid pointer dereference in io_ctl_map_page() when mounting and operating a crafted btrfs image, because of a lack of block group item validation in check_leaf_item in fs/btrfs/tree-checker.c (bnc#1102896).

CVE-2018-14617: There is a NULL pointer dereference and panic in hfsplus_lookup() in fs/hfsplus/dir.c when opening a file (that is purportedly a hard link) in an hfs+ filesystem that has malformed catalog data, and is mounted read-only without a metadata directory (bnc#1102870).

CVE-2018-16276: Local attackers could use user access read/writes with incorrect bounds checking in the yurex USB driver to crash the kernel or potentially escalate privileges (bnc#1106095 bnc#1115593).

CVE-2018-7757: Memory leak in the sas_smp_get_phy_events function in drivers/scsi/libsas/sas_expander.c allowed local users to cause a denial of service (memory consumption) via many read accesses to files in the /sys/class/sas_phy directory, as demonstrated by the /sys/class/sas_phy/phy-1:0:12/invalid_dword_count file (bnc#1087209).

CVE-2018-7480: The blkcg_init_queue function in block/blk-cgroup.c allowed local users to cause a denial of service (double free) or possibly have unspecified other impact by triggering a creation failure (bnc#1082863).

The update package also includes non-security fixes. See advisory for details.

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.

The SUSE Linux Enterprise 12 SP3 kernel was updated to 4.4.156 to receive various security and bugfixes.

The following security bugs were fixed :

CVE-2018-16597: Incorrect access checking in overlayfs mounts could have been used by local attackers to modify or truncate files in the underlying filesystem (bnc#1106512).

CVE-2018-14613: Prevent invalid pointer dereference in io_ctl_map_page() when mounting and operating a crafted btrfs image, caused by a lack of block group item validation in check_leaf_item (bsc#1102896)

CVE-2018-14617: Prevent NULL pointer dereference and panic in hfsplus_lookup() when opening a file (that is purportedly a hard link) in an hfs+ filesystem that has malformed catalog data, and is mounted read-only without a metadata directory (bsc#1102870)

CVE-2018-16276: Incorrect bounds checking in the yurex USB driver in yurex_read allowed local attackers to use user access read/writes to crash the kernel or potentially escalate privileges (bsc#1106095)

CVE-2018-7757: Memory leak in the sas_smp_get_phy_events function in drivers/scsi/libsas/sas_expander.c allowed local users to cause a denial of service (memory consumption) via many read accesses to files in the /sys/class/sas_phy directory, as demonstrated by the /sys/class/sas_phy/phy-1:0:12/invalid_dword_count file (bnc#1084536)

CVE-2018-7480: The blkcg_init_queue function allowed local users to cause a denial of service (double free) or possibly have unspecified other impact by triggering a creation failure (bsc#1082863).

CVE-2018-17182: The vmacache_flush_all function in mm/vmacache.c mishandled sequence number overflows. An attacker can trigger a use-after-free (and possibly gain privileges) via certain thread creation, map, unmap, invalidation, and dereference operations (bnc#1108399).

The update package also includes non-security fixes. See advisory for details.

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.

An update for kernel is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es) :

* It was found that the Linux kernel's IPv6 implementation mishandled socket options. A local attacker could abuse concurrent access to the socket options to escalate their privileges, or cause a denial of service (use-after-free and system crash) via a crafted sendmsg system call. (CVE-2016-3841, Important)

* Several Moderate and Low impact security issues were found in the Linux kernel. Space precludes documenting each of these issues in this advisory. Refer to the CVE links in the References section for a description of each of these vulnerabilities. (CVE-2013-4312, CVE-2015-8374, CVE-2015-8543, CVE-2015-8812, CVE-2015-8844, CVE-2015-8845, CVE-2016-2053, CVE-2016-2069, CVE-2016-2847, CVE-2016-3156, CVE-2016-4581, CVE-2016-4794, CVE-2016-5412, CVE-2016-5828, CVE-2016-5829, CVE-2016-6136, CVE-2016-6198, CVE-2016-6327, CVE-2016-6480, CVE-2015-8746, CVE-2015-8956, CVE-2016-2117, CVE-2016-2384, CVE-2016-3070, CVE-2016-3699, CVE-2016-4569, CVE-2016-4578)

Red Hat would like to thank Philip Pettersson (Samsung) for reporting CVE-2016-2053; Tetsuo Handa for reporting CVE-2016-2847; the Virtuozzo kernel team and Solar Designer (Openwall) for reporting CVE-2016-3156;
Justin Yackoski (Cryptonite) for reporting CVE-2016-2117; and Linn Crosetto (HP) for reporting CVE-2016-3699. The CVE-2015-8812 issue was discovered by Venkatesh Pottem (Red Hat Engineering); the CVE-2015-8844 and CVE-2015-8845 issues were discovered by Miroslav Vadkerti (Red Hat Engineering); the CVE-2016-4581 issue was discovered by Eric W. Biederman (Red Hat); the CVE-2016-6198 issue was discovered by CAI Qian (Red Hat); and the CVE-2016-3070 issue was discovered by Jan Stancek (Red Hat).

Additional Changes :

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.3 Release Notes linked from the References section.

ID	Name	Product	Family	Severity
126882	Slackware 14.2 : Slackware 14.2 kernel (SSA:2019-202-01)	Nessus	Slackware Local Security Checks	critical
126176	Photon OS 1.0: Linux PHSA-2019-1.0-0240	Nessus	PhotonOS Local Security Checks	high
124971	EulerOS Virtualization for ARM 64 3.0.1.0 : kernel (EulerOS-SA-2019-1518)	Nessus	Huawei Local Security Checks	high
121208	SUSE SLES12 Security Update : kernel (SUSE-SU-2019:0095-1)	Nessus	SuSE Local Security Checks	high
118194	openSUSE Security Update : the Linux Kernel (openSUSE-2018-1184)	Nessus	SuSE Local Security Checks	high
117933	SUSE SLED12 / SLES12 Security Update : kernel (SUSE-SU-2018:3003-1)	Nessus	SuSE Local Security Checks	high
95321	CentOS 7 : kernel (CESA-2016:2574)	Nessus	CentOS Local Security Checks	critical
94537	RHEL 7 : kernel (RHSA-2016:2574)	Nessus	Red Hat Local Security Checks	critical

Detections

Analytics

CVE-2018-16597

medium

Tenable Plugins

critical

high

high

high

high

high

critical

critical