Memory leak in hw/watchdog/wdt_i6300esb.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (host memory consumption and QEMU process crash) via a large number of device unplug operations.

The utrace support in Linux kernel 2.6.18, and other versions, allows local users to cause a denial of service (system hang) related to "MT exec + utrace_attach spin failure mode," as demonstrated by ptrace-thrash.c.

In the Linux kernel before 4.17, 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 mishandles ATTR_REPLACE operations with conversion of an attr from short to long form.

Double free vulnerability in the utrace support in the Linux kernel, probably 2.6.18, in Red Hat Enterprise Linux (RHEL) 5 and Fedora Core 6 (FC6) allows local users to cause a denial of service (oops), as demonstrated by a crash when running the GNU GDB testsuite, a different vulnerability than CVE-2008-2365.

The ehci_process_itd function in hw/usb/hcd-ehci.c in QEMU allows local guest OS administrators to cause a denial of service (infinite loop and CPU consumption) via a circular isochronous transfer descriptor (iTD) list.

net/sctp/sm_sideeffect.c in the Linux kernel before 4.3 does not properly manage the relationship between a lock and a socket, which allows local users to cause a denial of service (deadlock) via a crafted sctp_accept call.

NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability in firmware where the driver contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary, and may lead to denial of service or system crash.

The Linux kernel 2.6.24 and 2.6.25 before 2.6.25.9 allows local users to cause a denial of service (memory consumption) via a large number of calls to the get_user_pages function, which lacks a ZERO_PAGE optimization and results in allocation of "useless newly zeroed pages."

fs/overlayfs/copy_up.c in the Linux kernel before 4.2.6 uses an incorrect cleanup code path, which allows local users to cause a denial of service (dentry reference leak) via filesystem operations on a large file in a lower overlayfs layer.

The tm_reclaim_thread function in arch/powerpc/kernel/process.c in the Linux kernel before 4.4.1 on powerpc platforms does not ensure that TM suspend mode exists before proceeding with a tm_reclaim call, which allows local users to cause a denial of service (TM Bad Thing exception and panic) via a crafted application.

Integer overflow in the sctp_getsockopt_local_addrs_old function in net/sctp/socket.c in the Stream Control Transmission Protocol (sctp) functionality in the Linux kernel before 2.6.25.9 allows local users to cause a denial of service (resource consumption and system outage) via vectors involving a large addr_num field in an sctp_getaddrs_old data structure.

The fuse_fill_write_pages function in fs/fuse/file.c in the Linux kernel before 4.4 allows local users to cause a denial of service (infinite loop) via a writev system call that triggers a zero length for the first segment of an iov.

The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, 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 application that leverages a race condition between keyctl_revoke and keyctl_read calls.

ext4_protect_reserved_inode in fs/ext4/block_validity.c in the Linux kernel through 5.5.3 allows attackers to cause a denial of service (soft lockup) via a crafted journal size.

arch/x86/kvm/x86.c in the Linux kernel before 4.4 does not reset the PIT counter values during state restoration, which allows guest OS users to cause a denial of service (divide-by-zero error and host OS crash) via a zero value, related to the kvm_vm_ioctl_set_pit and kvm_vm_ioctl_set_pit2 functions.

An issue was discovered in the FUSE filesystem implementation in the Linux kernel before 5.10.6, aka CID-5d069dbe8aaf. fuse_do_getattr() calls make_bad_inode() in inappropriate situations, causing a system crash. NOTE: the original fix for this vulnerability was incomplete, and its incompleteness is tracked as CVE-2021-28950.

The clie_5_attach function in drivers/usb/serial/visor.c in the Linux kernel through 4.4.1 allows physically proximate attackers to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by inserting a USB device that lacks a bulk-out endpoint.

The ext4 implementation in the Linux kernel before 2.6.34 does not properly track the initialization of certain data structures, which allows physically proximate attackers to cause a denial of service (NULL pointer dereference and panic) via a crafted USB device, related to the ext4_fill_super function.

fs/ext4/namei.c in the Linux kernel before 3.7 allows physically proximate attackers to cause a denial of service (system crash) via a crafted no-journal filesystem, a related issue to CVE-2013-2015.

An issue was discovered in Xen through 4.10.x. Certain PV MMU operations may take a long time to process. For that reason Xen explicitly checks for the need to preempt the current vCPU at certain points. A few rarely taken code paths did bypass such checks. By suitably enforcing the conditions through its own page table contents, a malicious guest may cause such bypasses to be used for an unbounded number of iterations. A malicious or buggy PV guest may cause a Denial of Service (DoS) affecting the entire host. Specifically, it may prevent use of a physical CPU for an indeterminate period of time. All Xen versions from 3.4 onwards are vulnerable. Xen versions 3.3 and earlier are vulnerable to an even wider class of attacks, due to them lacking preemption checks altogether in the affected code paths. Only x86 systems are affected. ARM systems are not affected. Only multi-vCPU x86 PV guests can leverage the vulnerability. x86 HVM or PVH guests as well as x86 single-vCPU PV ones cannot leverage the vulnerability.

The slhc_init function in drivers/net/slip/slhc.c in the Linux kernel through 4.2.3 does not ensure that certain slot numbers are valid, which allows local users to cause a denial of service (NULL pointer dereference and system crash) via a crafted PPPIOCSMAXCID ioctl call.

arch/s390/kernel/ptrace.c in Linux kernel 2.6.9, and other versions before 2.6.27-rc6, on s390 platforms allows local users to cause a denial of service (kernel panic) via the user-area-padding test from the ptrace testsuite in 31-bit mode, which triggers an invalid dereference.

ntfs_read_locked_inode in the ntfs.ko filesystem driver in the Linux kernel 4.15.0 allows attackers to trigger a use-after-free read and possibly cause a denial of service (kernel oops or panic) via a crafted ntfs filesystem.

The Spectrum Scale 4.2.0.0 through 4.2.3.21 and 5.0.0.0 through 5.0.4.3 file system component is affected by a denial of service vulnerability in its kernel module that could allow an attacker to cause a denial of service condition on the affected system. To exploit this vulnerability, a local attacker could invoke a subset of ioctls on the Spectrum Scale device with non-valid arguments. This could allow the attacker to crash the kernel. IBM X-Force ID: 179986.

NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability in the kernel mode layer driver, where an invalid display configuration may lead to denial of service.

ip_nat_pptp in the PPTP NAT helper (netfilter/ip_nat_helper_pptp.c) in Linux kernel 2.6.14, and other versions, allows local users to cause a denial of service (memory corruption or crash) via a crafted outbound packet that causes an incorrect offset to be calculated from pointer arithmetic when non-linear SKBs (socket buffers) are used.

fs/direct-io.c in the dio subsystem in the Linux kernel before 2.6.23 does not properly zero out the dio struct, which allows local users to cause a denial of service (OOPS), as demonstrated by a certain fio test.

The Linux kernel through 6.1.9 has a Use-After-Free in bigben_remove in drivers/hid/hid-bigbenff.c via a crafted USB device because the LED controllers remain registered for too long.

The perf_callchain_user_64 function in arch/powerpc/perf/callchain.c in the Linux kernel before 4.0.2 on ppc64 platforms allows local users to cause a denial of service (infinite loop) via a deep 64-bit userspace backtrace.

An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are processing watch events using a single thread. If the events are received faster than the thread is able to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable.

An issue was discovered in Xen 4.6 through 4.14.x. When acting upon a guest XS_RESET_WATCHES request, not all tracking information is freed. A guest can cause unbounded memory usage in oxenstored. This can lead to a system-wide DoS. Only systems using the Ocaml Xenstored implementation are vulnerable. Systems using the C Xenstored implementation are not vulnerable.

An issue was discovered in drivers/accessibility/speakup/spk_ttyio.c in the Linux kernel through 5.9.9. Local attackers on systems with the speakup driver could cause a local denial of service attack, aka CID-d41227544427. This occurs because of an invalid free when the line discipline is used more than once.

An issue was discovered in Xen through 4.14.x. A guest may access xenstore paths via absolute paths containing a full pathname, or via a relative path, which implicitly includes /local/domain/$DOMID for their own domain id. Management tools must access paths in guests' namespaces, necessarily using absolute paths. oxenstored imposes a pathname limit that is applied solely to the relative or absolute path specified by the client. Therefore, a guest can create paths in its own namespace which are too long for management tools to access. Depending on the toolstack in use, a malicious guest administrator might cause some management tools and debugging operations to fail. For example, a guest administrator can cause "xenstore-ls -r" to fail. However, a guest administrator cannot prevent the host administrator from tearing down the domain. All systems using oxenstored are vulnerable. Building and using oxenstored is the default in the upstream Xen distribution, if the Ocaml compiler is available. Systems using C xenstored are not vulnerable.

An issue was discovered in Xen through 4.10.x allowing x86 HVM guest OS users to cause a denial of service (host OS infinite loop) in situations where a QEMU device model attempts to make invalid transitions between states of a request.

An issue was discovered in Xen through 4.14.x. When they require assistance from the device model, x86 HVM guests must be temporarily de-scheduled. The device model will signal Xen when it has completed its operation, via an event channel, so that the relevant vCPU is rescheduled. If the device model were to signal Xen without having actually completed the operation, the de-schedule / re-schedule cycle would repeat. If, in addition, Xen is resignalled very quickly, the re-schedule may occur before the de-schedule was fully complete, triggering a shortcut. This potentially repeating process uses ordinary recursive function calls, and thus could result in a stack overflow. A malicious or buggy stubdomain serving a HVM guest can cause Xen to crash, resulting in a Denial of Service (DoS) to the entire host. Only x86 systems are affected. Arm systems are not affected. Only x86 stubdomains serving HVM guests can exploit the vulnerability.

The etm_setup_aux function in drivers/hwtracing/coresight/coresight-etm-perf.c in the Linux kernel before 4.10.2 allows attackers to cause a denial of service (panic) because a parameter is incorrectly used as a local variable.

The __rds_conn_create function in net/rds/connection.c in the Linux kernel through 4.2.3 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by using a socket that was not properly bound.

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. Guest OS users can cause a denial of service (host OS hang) via a high rate of events to dom0, aka CID-e99502f76271.

A flaw was found in the Linux kernel's ext4 filesystem. A local user can cause an out-of-bound access in ext4_get_group_info function, a denial of service, and a system crash by mounting and operating on a crafted ext4 filesystem image.

A flaw was found in Linux kernel in the ext4 filesystem code. A use-after-free is possible in ext4_ext_remove_space() function when mounting and operating a crafted ext4 image.

The Xen hypervisor block backend driver for Linux kernel 2.6.18, when running on a 64-bit host with a 32-bit paravirtualized guest, allows local privileged users in the guest OS to cause a denial of service (host OS crash) via a request that specifies a large number of blocks.

An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in Xen, 32-bit domains (including Domain 0) servicing other domains may observe event channel allocations to succeed when they should really fail. Subsequent use of such event channels would then possibly lead to corruption of other parts of the shared info structure. An unprivileged guest may cause another domain, in particular Domain 0, to misbehave. This may lead to a Denial of Service (DoS) for the entire system. All Xen versions from 4.4 onwards are vulnerable. Xen versions 4.3 and earlier are not vulnerable. Only x86 32-bit domains servicing other domains are vulnerable. Arm systems, as well as x86 64-bit domains, are not vulnerable.

In kdeconnect-kde (aka KDE Connect) before 20.08.2, an attacker on the local network could send crafted packets that trigger use of large amounts of CPU, memory, or network connection slots, aka a Denial of Service attack.

A flaw memory leak in the Linux kernel performance monitoring subsystem was found in the way if using PERF_EVENT_IOC_SET_FILTER. A local user could use this flaw to starve the resources causing denial of service.

The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a denial of service (host OS panic or hang) by triggering many #AC (aka Alignment Check) exceptions, related to svm.c and vmx.c.

An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchn_reset() / evtchn_destroy(). In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these (when resetting all event channels or when cleaning up after the guest) may take extended periods of time. So far, there was no arrangement for preemption at suitable intervals, allowing a CPU to spend an almost unbounded amount of time in the processing of these operations. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system. All Xen versions are vulnerable in principle. Whether versions 4.3 and older are vulnerable depends on underlying hardware characteristics.