important: libssh2/kernel-rt security update
important
An update for libssh2/kernel-rt is now available for NewStart CGSL MAIN 5.04/CGSL CORE 5.04.
NewStart Security has rated this update as having a security impact of important. A Common Vunlnerability Scoring System(CVSS)base score, which gives a detailed severity rating, is available for each vulnerability from the CVElink(s) in the References section.
libssh2: libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).
kernel-rt: The kernel-rt package contains the Linux kernel (vmlinuz), the core of any Linux operating system. The kernel handles the basic functions of the operating system: memory allocation, process allocation, device input and output, etc. This kernel has been compiled with the RT patch applied and is intended for use in deterministic response-time situations
Security Fix(es):
libssh2: An out of bounds read flaw was discovered in libssh2 in the way SSH_MSG_CHANNEL_REQUEST packets with an exit status message and no payload are parsed. A remote attacker who compromises a SSH server may be able to cause a denial of service or read data in the client memory.(CVE-2019-3862)
libssh2: bugfix
kernel-rt: A flaw was found in the way Linux kernel KVM hypervisor emulated instructions such as sgdt/sidt/fxsave/fxrstor. It did not check current privilege(CPL) level while emulating unprivileged instructions. An unprivileged guest user/process could use this flaw to potentially escalate privileges inside guest.(CVE-2018-10853)
kernel-rt: A flaw was found where an attacker may be able to have an uncontrolled read to kernel-memory from within a vm guest. A race condition between connect() and close() function may allow an attacker using the AF_VSOCK protocol to gather a 4 byte information leak or possibly impersonate AF_VSOCK messages destined to other clients or leak kernel memory.(CVE-2018-14625)
kernel-rt: A flaw was found in the Linux Kernel in the ucma_leave_multicast() function in drivers/infiniband/core/ucma.c which allows access to a certain data structure after freeing it in ucma_process_join(). This allows an attacker to cause a use-after-free bug and to induce kernel memory corruption, leading to a system crash or other unspecified impact. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is unlikely.(CVE-2018-14734)
kernel-rt: It was found that paravirt_patch_call/jump() functions in the arch/x86/kernel/paravirt.c in the Linux kernel mishandles certain indirect calls, which makes it easier for attackers to conduct Spectre-v2 attacks against paravirtualized guests.(CVE-2018-15594)
kernel-rt: A flaw was found in the Linux kernel's NFS implementation. An attacker, who is able to mount an exported NFS filesystem, is able to trigger a null pointer dereference by using an invalid NFS sequence. This can panic the machine and deny access to the NFS server. Any outstanding disk writes to the NFS server will be lost.(CVE-2018-16871)
kernel-rt: A flaw was found in the Linux kernel's NFS41+ subsystem. NFS41+ shares mounted in different network namespaces at the same time can make bc_svc_process() use wrong back-channel IDs and cause a use-after-free vulnerability. Thus a malicious container user can cause a host kernel memory corruption and a system panic. Due to the nature of the flaw, privilege escalation cannot be fully ruled out.(CVE-2018-16884)
kernel-rt: Since Linux kernel version 3.2, 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.(CVE-2018-18281)
kernel-rt: A buffer overflow due to a singed-unsigned comparsion was found in hidp_process_report() in the net/bluetooth/hidp/core.c in the Linux kernel. The buffer length is an unsigned int but gets cast to a signed int which in certain conditions can lead to a system panic and a denial-of-service.(CVE-2018-9363)
kernel-rt: A race condition between pppol2tp_session_create() and l2tp_eth_create() in net/l2tp/l2tp_netlink.c was found in the Linux kernel. Calling l2tp_tunnel_find() may result in a new tunnel being created with tunnel id of a previously removed tunnel which wouldn't be protected by the reference counter.(CVE-2018-9517)
kernel-rt: A flaw was found in the Linux kernel's implementation of GVT-g which allowed an attacker with access to a 'passed through' Intel i915 graphics card to possibly access resources allocated to other virtual machines, crash the host, or possibly corrupt memory leading to privilege escalation.(CVE-2019-11085)
kernel-rt: A flaw was found in the Linux kernel where the coredump implementation does not use locking or other mechanisms to prevent vma layout or vma flags changes while it runs. This allows local users to obtain sensitive information, cause a denial of service (DoS), or possibly have unspecified other impact by triggering a race condition with mmget_not_zero or get_task_mm calls.(CVE-2019-11599)
kernel-rt: A flaw was found in the Linux kernel, prior to version 5.0.7, in drivers/scsi/megaraid/megaraid_sas_base.c, where a NULL pointer dereference can occur when megasas_create_frame_pool() fails in megasas_alloc_cmds(). An attacker can crash the system if they were able to load the megaraid_sas kernel module and groom memory beforehand, leading to a denial of service (DoS), related to a use-after-free.(CVE-2019-11810)
kernel-rt: A flaw was found in the Linux kernel's implementation of IPMI (remote baseband access). An attacker, with local access to read /proc/ioports, may be able to create a use-after-free condition when the kernel module is unloaded which may result in privilege escalation.(CVE-2019-11811)
kernel-rt: A flaw was found in the Linux kernel's implementation of ext4 extent management. The kernel doesn't correctly initialize memory regions in the extent tree block which may be exported to a local user to obtain sensitive information by reading empty/uninitialized data from the filesystem.(CVE-2019-11833)
kernel-rt: A flaw was found in the Linux kernel's implementation of Logical Link Control and Adaptation Protocol (L2CAP), part of the Bluetooth stack. An attacker, within the range of standard Bluetooth transmissions, can create and send a specially crafted packet. The response to this specially crafted packet can contain part of the kernel stack which can be used in a further attack.(CVE-2019-3459)
kernel-rt: A flaw was found in the Linux kernel's implementation of logical link control and adaptation protocol (L2CAP), part of the Bluetooth stack in the l2cap_parse_conf_rsp and l2cap_parse_conf_req functions. An attacker with physical access within the range of standard Bluetooth transmission can create a specially crafted packet. The response to this specially crafted packet can contain part of the kernel stack which can be used in a further attack.(CVE-2019-3460)
kernel-rt: A flaw was found in the Linux kernel's vfio interface implementation that permits violation of the user's locked memory limit. If a device is bound to a vfio driver, such as vfio-pci, and the local attacker is administratively granted ownership of the device, it may cause a system memory exhaustion and thus a denial of service (DoS).(CVE-2019-3882)
kernel-rt: An infinite loop issue was found in the vhost_net kernel module while handling incoming packets in handle_rx(). The infinite loop could occur if one end sends packets faster than the other end can process them. A guest user, maybe a remote one, could use this flaw to stall the vhost_net kernel thread, resulting in a DoS scenario.(CVE-2019-3900)
kernel-rt: A new software page cache side channel attack scenario was discovered in operating systems that implement the very common 'page cache' caching mechanism. A malicious user/process could use 'in memory' page-cache knowledge to infer access timings to shared memory and gain knowledge which can be used to reduce effectiveness of cryptographic strength by monitoring algorithmic behavior, infer access patterns of memory to determine code paths taken, and exfiltrate data to a blinded attacker through page-granularity access times as a side-channel.(CVE-2019-5489)
kernel-rt: bugfix
Solution:
For details on how to apply this update, which includes the changes described in this advisory, refer to:
http://security.gd-linux.com/how_to_apply_patch.html
Remember the build tag is 5.04.F17.