The Linux kernel component in IBM PowerKVM 2.1 before 2.1.1.3-65.10 and 3.1 before 3.1.0.2 allows guest OS users to cause a denial of service (host OS infinite loop and hang) via unspecified vectors.

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.

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2016:1033 advisory.

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

    Security Fix(es):

    * A flaw was found in the way the Linux kernel's ASN.1 DER decoder processed certain certificate files     with tags of indefinite length. A local, unprivileged user could use a specially crafted X.509 certificate     DER file to crash the system or, potentially, escalate their privileges on the system. (CVE-2016-0758,     Important)

    Red Hat would like to thank Philip Pettersson of Samsung for reporting this issue.

    Bug Fix(es):

    * Under certain conditions, the migration threads could race with the CPU hotplug, which could cause a     deadlock. A set of patches has been provided to fix this bug, and the deadlock no longer occurs in the     system. (BZ#1299338)

    * A bug in the code that cleans up revoked delegations could previously cause a soft lockup in the NFS     server. This patch fixes the underlying source code, so the lockup no longer occurs. (BZ#1311582)

    * The second attempt to reload Common Application Programming Interface (CAPI) devices on the little-     endian variant of IBM Power Systems previously failed. The provided set of patches fixes this bug, and     reloading works as intended. (BZ#1312396)

    * Due to inconsistencies in page size of IOMMU, the NVMe device, and the kernel, the BUG_ON signal     previously occurred in the nvme_setup_prps() function, leading to the system crash while setting up the     DMA transfer. The provided patch sets the default NVMe page size to 4k, thus preventing the system crash.
    (BZ#1312399)

    * Previously, on a system using the Infiniband mlx5 driver used for the SRP stack, a hard lockup     previously occurred after the kernel exceeded time with lock held with interrupts blocked. As a     consequence, the system panicked. This update fixes this bug, and the system no longer panics in this     situation. (BZ#1313814)

    * On the little-endian variant of IBM Power Systems, the kernel previously crashed in the bitmap_weight()     function while running the memory affinity script. The provided patch fortifies the topology setup and     prevents sd->child from being set to NULL when it is already NULL. As a result, the memory affinity script     runs successfully. (BZ#1316158)

    * When a KVM guest wrote random values to the special-purpose registers (SPR) Instruction Authority Mask     Register (IAMR), the guest and the corresponding QEMU process previously hung. This update adds the code     which sets SPRs to a suitable neutral value on guest exit, thus fixing this bug. (BZ#1316636)

    * Under heavy iSCSI traffic load, the system previously panicked due to a race in the locking code leading     to a list corruption. This update fixes this bug, and the system no longer panics in this situation.
    (BZ#1316812)

    * During SCSI exception handling (triggered by some irregularities), the driver could previously use an     already retired SCSI command. As a consequence, a kernel panic or data corruption occurred. The provided     patches fix this bug, and exception handling now proceeds successfully. (BZ#1316820)

    * When the previously opened /dev/tty, which pointed to a pseudo terminal (pty) pair, was the last file     closed, a kernel crash could previously occur. The underlying source code has been fixed, preventing this     bug. (BZ#1320297)

    * Previously, when using VPLEX and FCoE via the bnx2fc driver, different degrees of data corruption     occurred. The provided patch fixes the FCP Response (RSP) residual parsing in bnx2fc, which prevents the     aforementioned corruption. (BZ#1322279)

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

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) :

* A flaw was found in the way the Linux kernel's ASN.1 DER decoder processed certain certificate files with tags of indefinite length. A local, unprivileged user could use a specially crafted X.509 certificate DER file to crash the system or, potentially, escalate their privileges on the system. (CVE-2016-0758, Important)

Red Hat would like to thank Philip Pettersson of Samsung for reporting this issue.

Bug Fix(es) :

* Under certain conditions, the migration threads could race with the CPU hotplug, which could cause a deadlock. A set of patches has been provided to fix this bug, and the deadlock no longer occurs in the system. (BZ# 1299338)

* A bug in the code that cleans up revoked delegations could previously cause a soft lockup in the NFS server. This patch fixes the underlying source code, so the lockup no longer occurs. (BZ#1311582)

* The second attempt to reload Common Application Programming Interface (CAPI) devices on the little-endian variant of IBM Power Systems previously failed. The provided set of patches fixes this bug, and reloading works as intended. (BZ#1312396)

* Due to inconsistencies in page size of IOMMU, the NVMe device, and the kernel, the BUG_ON signal previously occurred in the nvme_setup_prps() function, leading to the system crash while setting up the DMA transfer. The provided patch sets the default NVMe page size to 4k, thus preventing the system crash. (BZ#1312399)

* Previously, on a system using the Infiniband mlx5 driver used for the SRP stack, a hard lockup previously occurred after the kernel exceeded time with lock held with interrupts blocked. As a consequence, the system panicked. This update fixes this bug, and the system no longer panics in this situation. (BZ#1313814)

* On the little-endian variant of IBM Power Systems, the kernel previously crashed in the bitmap_weight() function while running the memory affinity script. The provided patch fortifies the topology setup and prevents sd-> child from being set to NULL when it is already NULL. As a result, the memory affinity script runs successfully. (BZ#1316158)

* When a KVM guest wrote random values to the special-purpose registers (SPR) Instruction Authority Mask Register (IAMR), the guest and the corresponding QEMU process previously hung. This update adds the code which sets SPRs to a suitable neutral value on guest exit, thus fixing this bug. (BZ#1316636)

* Under heavy iSCSI traffic load, the system previously panicked due to a race in the locking code leading to a list corruption. This update fixes this bug, and the system no longer panics in this situation. (BZ#1316812)

* During SCSI exception handling (triggered by some irregularities), the driver could previously use an already retired SCSI command. As a consequence, a kernel panic or data corruption occurred. The provided patches fix this bug, and exception handling now proceeds successfully. (BZ #1316820)

* When the previously opened /dev/tty, which pointed to a pseudo terminal (pty) pair, was the last file closed, a kernel crash could previously occur. The underlying source code has been fixed, preventing this bug. (BZ# 1320297)

* Previously, when using VPLEX and FCoE via the bnx2fc driver, different degrees of data corruption occurred. The provided patch fixes the FCP Response (RSP) residual parsing in bnx2fc, which prevents the aforementioned corruption. (BZ#1322279)

ID	Name	Product	Family	Severity
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
91114	RHEL 7 : kernel (RHSA-2016:1033)	Nessus	Red Hat Local Security Checks	high
91105	CentOS 7 : kernel (CESA-2016:1033)	Nessus	CentOS Local Security Checks	high

Detections

Analytics

CVE-2016-3044

medium

Tenable Plugins

critical

critical

high

high