An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

An integer overflow issue was found in the vmxnet3 NIC emulator of the QEMU for versions up to v5.2.0. It may occur if a guest was to supply invalid values for rx/tx queue size or other NIC parameters. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

A flaw was found in NetworkManager in versions before 1.30.0. Setting match.path and activating a profile crashes NetworkManager. The highest threat from this vulnerability is to system availability.

fedup 0.9.0 in Fedora 19, 20, and 21 uses a temporary directory with a static name for its download cache, which allows local users to cause a denial of service (prevention of system updates).

A vulnerability was found in libX11 due to an infinite loop within the PutSubImage() function. This flaw allows a local user to consume all available system resources and cause a denial of service condition.

An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It ignores the top byte in the address passed to the brk system call, potentially moving the memory break downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to cause heap corruption with the GNU C Library malloc implementation.

Improper buffer restrictions in the firmware of Intel(R) Ethernet Adapters 800 Series Controllers and associated adapters before version 1.5.3.0 may allow a privileged user to potentially enable denial of service via local access.

tuned before 2.x allows local users to kill running processes due to insecure permissions with tuned's ktune service.

The GNU C Library (aka glibc or libc6) before 2.32 could overflow an on-stack buffer during range reduction if an input to an 80-bit long double function contains a non-canonical bit pattern, a seen when passing a 0x5d414141414141410000 value to sinl on x86 targets. This is related to sysdeps/ieee754/ldbl-96/e_rem_pio2l.c.

A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.

tuned 2.10.0 creates its PID file with insecure permissions which allows local users to kill arbitrary processes.

The PV domain builder in Xen 4.2 and earlier does not validate the size of the kernel or ramdisk (1) before or (2) after decompression, which allows local guest administrators to cause a denial of service (domain 0 memory consumption) via a crafted (a) kernel or (b) ramdisk.

The (1) domain_pirq_to_emuirq and (2) physdev_unmap_pirq functions in Xen 2.2 allows local guest OS administrators to cause a denial of service (Xen crash) via a crafted pirq value that triggers an out-of-bounds read.

Xen 4.0 through 4.2, when running 32-bit x86 PV guests on 64-bit hypervisors, allows local guest OS administrators to cause a denial of service (infinite loop and hang or crash) via invalid arguments to GNTTABOP_get_status_frames, aka "Grant table hypercall infinite loop DoS vulnerability."

Xen 3.4 through 4.2, and possibly earlier versions, does not properly synchronize the p2m and m2p tables when the set_p2m_entry function fails, which allows local HVM guest OS administrators to cause a denial of service (memory consumption and assertion failure), aka "Memory mapping failure DoS vulnerability."

A use-after-free vulnerability was found in the cyttsp4_core driver in the Linux kernel. This issue occurs in the device cleanup routine due to a possible rearming of the watchdog_timer from the workqueue. This could allow a local user to crash the system, causing a denial of service.

A use-after-free vulnerability was found in the siano smsusb module in the Linux kernel. The bug occurs during device initialization when the siano device is plugged in. This flaw allows a local user to crash the system, causing a denial of service condition.

The set_debugreg hypercall in include/asm-x86/debugreg.h in Xen 4.0, 4.1, and 4.2, and Citrix XenServer 6.0.2 and earlier, when running on x86-64 systems, allows local OS guest users to cause a denial of service (host crash) by writing to the reserved bits of the DR7 debug control register.

Redis is an in-memory database that persists on disk. Prior to versions 6.2.7 and 7.0.0, an attacker attempting to load a specially crafted Lua script can cause NULL pointer dereference which will result with a crash of the redis-server process. The problem is fixed in Redis versions 7.0.0 and 6.2.7. An additional workaround to mitigate this problem without patching the redis-server executable, if Lua scripting is not being used, is to block access to `SCRIPT LOAD` and `EVAL` commands using ACL rules.

A use-after-free vulnerability was found in the cxgb4 driver in the Linux kernel. The bug occurs when the cxgb4 device is detaching due to a possible rearming of the flower_stats_timer from the work queue. This flaw allows a local user to crash the system, causing a denial of service condition.

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.

A NULL pointer dereference flaw was found in the SCSI emulation support of QEMU in versions before 6.0.0. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

libvips is a demand-driven, horizontally threaded image processing library. A specially crafted SVG input can cause libvips versions 8.14.3 or earlier to segfault when attempting to parse a malformed UTF-8 character. Users should upgrade to libvips version 8.14.4 (or later) when processing untrusted input.

A NULL pointer dereference flaw was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU in versions before and including 6.0. This issue occurs in the megasas_command_cancelled() callback function while dropping a SCSI request. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

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 out-of-bounds read flaw was found in Shim due to the lack of proper boundary verification during the load of a PE binary. This flaw allows an attacker to load a crafted PE binary, triggering the issue and crashing Shim, resulting in a denial of service.

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.

In musl libc through 1.2.1, wcsnrtombs mishandles particular combinations of destination buffer size and source character limit, as demonstrated by an invalid write access (buffer overflow).

Oxenstored 32->31 bit integer truncation issues Integers in Ocaml are 63 or 31 bits of signed precision. The Ocaml Xenbus library takes a C uint32_t out of the ring and casts it directly to an Ocaml integer. In 64-bit Ocaml builds this is fine, but in 32-bit builds, it truncates off the most significant bit, and then creates unsigned/signed confusion in the remainder. This in turn can feed a negative value into logic not expecting a negative value, resulting in unexpected exceptions being thrown. The unexpected exception is not handled suitably, creating a busy-loop trying (and failing) to take the bad packet out of the xenstore ring.

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.

The Oberthur smart card software driver in OpenSC before 0.21.0-rc1 has a heap-based buffer overflow in sc_oberthur_read_file.

The TCOS smart card software driver in OpenSC before 0.21.0-rc1 has a stack-based buffer overflow in tcos_decipher.

The gemsafe GPK smart card software driver in OpenSC before 0.21.0-rc1 has a stack-based buffer overflow in sc_pkcs15emu_gemsafeGPK_init.

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 way the spice-vdagentd daemon handled file transfers from the host system to the virtual machine. Any unprivileged local guest user with access to the UNIX domain socket path `/run/spice-vdagentd/spice-vdagent-sock` could use this flaw to perform a memory denial of service for spice-vdagentd or even other processes in the VM system. The highest threat from this vulnerability is to system availability. This flaw affects spice-vdagent versions 0.20 and previous versions.

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.

A flaw was found in the spice-vdagentd daemon, where it did not properly handle client connections that can be established via the UNIX domain socket in `/run/spice-vdagentd/spice-vdagent-sock`. Any unprivileged local guest user could use this flaw to prevent legitimate agents from connecting to the spice-vdagentd daemon, resulting in a denial of service. The highest threat from this vulnerability is to system availability. This flaw affects spice-vdagent versions 0.20 and prior.

A vulnerability was found in Linux kernel where non-blocking socket in llcp_sock_connect() leads to leak and eventually hanging-up the system.

An issue was discovered in Xen through 4.14.x. x86 PV guest kernels can experience denial of service via SYSENTER. The SYSENTER instruction leaves various state sanitization activities to software. One of Xen's sanitization paths injects a #GP fault, and incorrectly delivers it twice to the guest. This causes the guest kernel to observe a kernel-privilege #GP fault (typically fatal) rather than a user-privilege #GP fault (usually converted into SIGSEGV/etc.). Malicious or buggy userspace can crash the guest kernel, resulting in a VM Denial of Service. All versions of Xen from 3.2 onwards are vulnerable. Only x86 systems are vulnerable. ARM platforms are not vulnerable. Only x86 systems that support the SYSENTER instruction in 64bit mode are vulnerable. This is believed to be Intel, Centaur, and Shanghai CPUs. AMD and Hygon CPUs are not believed to be vulnerable. Only x86 PV guests can exploit the vulnerability. x86 PVH / HVM guests cannot exploit the vulnerability.

A flaw was found in Shim when an error happened while creating a new ESL variable. If Shim fails to create the new variable, it tries to print an error message to the user; however, the number of parameters used by the logging function doesn't match the format string used by it, leading to a crash under certain circumstances.

Vixie Cron before the 3.0pl1-133 Debian package allows local users to cause a denial of service (daemon crash) via a large crontab file because the calloc return value is not checked.

Vixie Cron before the 3.0pl1-133 Debian package allows local users to cause a denial of service (memory consumption) via a large crontab file because an unlimited number of lines is accepted.

An issue was discovered in sd-bus in systemd 239. bus_process_object() in libsystemd/sd-bus/bus-objects.c allocates a variable-length stack buffer for temporarily storing the object path of incoming D-Bus messages. An unprivileged local user can exploit this by sending a specially crafted message to PID1, causing the stack pointer to jump over the stack guard pages into an unmapped memory region and trigger a denial of service (systemd PID1 crash and kernel panic).

In QEMU 3.1, scsi_handle_inquiry_reply in hw/scsi/scsi-generic.c allows out-of-bounds write and read operations.

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). Versions 3.10, 4.14 and 4.18 are vulnerable.

The mem_cgroup_usage_unregister_event function in mm/memcontrol.c in the Linux kernel before 3.2.10 does not properly handle multiple events that are attached to the same eventfd, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by registering memory threshold events.

A flaw was found in the Linux kernel’s IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to directly dereference a NULL pointer in xfrm_update_ae_params(), leading to a possible kernel crash and denial of service.

An issue was discovered in button_open in login/logind-button.c in systemd before 243. When executing the udevadm trigger command, a memory leak may occur.