Linux Kernel

net/packet/af_packet.c in the Linux kernel before 4.13.6 allows local users to gain privileges via crafted system calls that trigger mishandling of packet_fanout data structures, because of a race condition (involving fanout_add and packet_do_bind) that leads to a use-after-free, a different vulnerability than CVE-2017-6346.Show less

The x86/fpu (Floating Point Unit) subsystem in the Linux kernel before 4.13.5, when a processor supports the xsave feature but not the xsaves feature, does not correctly handle attempts to set reserved bits in the xstate header via the ptrace() or rt_sigreturn() system call, allowing local users to read the FPU registers of other processes on the system, related to arch/x86/kernel/fpu/regset.c and arch/x86/kernel/fpu/signal.c.Show less

Race condition in the ALSA subsystem in the Linux kernel before 4.13.8 allows local users to cause a denial of service (use-after-free) or possibly have unspecified other impact via crafted /dev/snd/seq ioctl calls, related to sound/core/seq/seq_clientmgr.c and sound/core/seq/seq_ports.c.Show less

The KEYS subsystem in the Linux kernel through 4.13.7 mishandles use of add_key for a key that already exists but is uninstantiated, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted system call.Show less

security/keys/keyctl.c in the Linux kernel before 4.11.5 does not consider the case of a NULL payload in conjunction with a nonzero length value, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) via a crafted add_key or keyctl system call, a different vulnerability than CVE-2017-12192.Show less

The keyctl_read_key function in security/keys/keyctl.c in the Key Management subcomponent in the Linux kernel before 4.13.5 does not properly consider that a key may be possessed but negatively instantiated, which allows local users to cause a denial of service (OOPS and system crash) via a crafted KEYCTL_READ operation.Show less

arch/x86/kvm/mmu.c in the Linux kernel through 4.13.5, when nested virtualisation is used, does not properly traverse guest pagetable entries to resolve a guest virtual address, which allows L1 guest OS users to execute arbitrary code on the host OS or cause a denial of service (incorrect index during page walking, and host OS crash), aka an "MMU potential stack buffer overrun."Show less

Linux distributions that have not patched their long-term kernels with https://git.kernel.org/linus/a87938b2e246b81b4fb713edb371a9fa3c5c3c86 (committed on April 14, 2015). This kernel vulnerability was fixed in April 2015 by commit a87938b2e246b81b4fb713edb371a9fa3c5c3c86 (backported to Linux 3.10.77 in May 2015), but it was not recognized as a security threat. With CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE enabled, and a normal top-down address allocation strategy, load_elf_binary() will attempt to map a PIE binary into an address range immediately below mm->mmap_base. Unfortunately, load_elf_ binary() does not take account of the need to allocate sufficient space for the entire binary which means that, while the first PT_LOAD segment is mapped below mm->mmap_base, the subsequent PT_LOAD segment(s) end up being mapped above mm->mmap_base into the are that is supposed to be the "gap" between the stack and the binary.Show less

Linux kernel: Exploitable memory corruption due to UFO to non-UFO path switch. When building a UFO packet with MSG_MORE __ip_append_data() calls ip_ufo_append_data() to append. However in between two send() calls, the append path can be switched from UFO to non-UFO one, which leads to a memory corruption. In case UFO packet lengths exceeds MTU, copy = maxfraglen - skb->len becomes negative on the non-UFO path and the branch to allocate new skb is taken. This triggers fragmentation and computation of fraggap = skb_prev->len - maxfraglen. Fraggap can exceed MTU, causing copy = datalen - transhdrlen - fraggap to become negative. Subsequently skb_copy_and_csum_bits() writes out-of-bounds. A similar issue is present in IPv6 code. The bug was introduced in e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") on Oct 18 2005.Show less

Linux kernel: heap out-of-bounds in AF_PACKET sockets. This new issue is analogous to previously disclosed CVE-2016-8655. In both cases, a socket option that changes socket state may race with safety checks in packet_set_ring. Previously with PACKET_VERSION. This time with PACKET_RESERVE. The solution is similar: lock the socket for the update. This issue may be exploitable, we did not investigate further. As this issue affects PF_PACKET sockets, it requires CAP_NET_RAW in the process namespace. But note that with user namespaces enabled, any process can create a namespace in which it has CAP_NET_RAW.Show less

The sg_ioctl function in drivers/scsi/sg.c in the Linux kernel before 4.13.4 allows local users to obtain sensitive information from uninitialized kernel heap-memory locations via an SG_GET_REQUEST_TABLE ioctl call for /dev/sg0.Show less

The waitid implementation in kernel/exit.c in the Linux kernel through 4.13.4 accesses rusage data structures in unintended cases, which allows local users to obtain sensitive information, and bypass the KASLR protection mechanism, via a crafted system call.Show less

The prepare_vmcs02 function in arch/x86/kvm/vmx.c in the Linux kernel through 4.13.3 does not ensure that the "CR8-load exiting" and "CR8-store exiting" L0 vmcs02 controls exist in cases where L1 omits the "use TPR shadow" vmcs12 control, which allows KVM L2 guest OS users to obtain read and write access to the hardware CR8 register.Show less

The KVM subsystem in the Linux kernel through 4.13.3 allows guest OS users to cause a denial of service (assertion failure, and hypervisor hang or crash) via an out-of bounds guest_irq value, related to arch/x86/kvm/vmx.c and virt/kvm/eventfd.c.Show less

A security flaw was discovered in the nl80211_set_rekey_data() function in net/wireless/nl80211.c in the Linux kernel through 4.13.3. This function does not check whether the required attributes are present in a Netlink request. This request can be issued by a user with the CAP_NET_ADMIN capability and may result in a NULL pointer dereference and system crash.Show less

The access_pmu_evcntr function in arch/arm64/kvm/sys_regs.c in the Linux kernel before 4.8.11 allows privileged KVM guest OS users to cause a denial of service (assertion failure and host OS crash) by accessing the Performance Monitors Cycle Count Register (PMCCNTR).Show less

The tpacket_rcv function in net/packet/af_packet.c in the Linux kernel before 4.13 mishandles vnet headers, which might allow local users to cause a denial of service (buffer overflow, and disk and memory corruption) or possibly have unspecified other impact via crafted system calls.Show less

The XFS_IS_REALTIME_INODE macro in fs/xfs/xfs_linux.h in the Linux kernel before 4.13.2 does not verify that a filesystem has a realtime device, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) via vectors related to setting an RHINHERIT flag on a directory.Show less