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 kernel_wait4 function in kernel/exit.c in the Linux kernel before 4.13, when an unspecified architecture and compiler is used, might allow local users to cause a denial of service by triggering an attempted use of the -INT_MIN value.

The manager_invoke_notify_message function in systemd 231 and earlier allows local users to cause a denial of service (assertion failure and PID 1 hang) via a zero-length message received over a notify socket.

The ne2000_receive function in the NE2000 NIC emulation support (hw/net/ne2000.c) in QEMU before 2.5.1 allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via crafted values for the PSTART and PSTOP registers, involving ring buffer control.

Various memory and file descriptor leaks were found in apt-python files python/arfile.cc, python/tag.cc, python/tarfile.cc, aka GHSL-2020-170. This issue affects: python-apt 1.1.0~beta1 versions prior to 1.1.0~beta1ubuntu0.16.04.10; 1.6.5ubuntu0 versions prior to 1.6.5ubuntu0.4; 2.0.0ubuntu0 versions prior to 2.0.0ubuntu0.20.04.2; 2.1.3ubuntu1 versions prior to 2.1.3ubuntu1.1;

Aptdaemon performed policykit checks after interacting with potentially untrusted files with elevated privileges. This affected versions prior to 1.1.1+bzr982-0ubuntu34.1, 1.1.1+bzr982-0ubuntu32.3, 1.1.1+bzr982-0ubuntu19.5, 1.1.1+bzr982-0ubuntu14.5.

An issue was discovered in Xen 4.14.x. There is a missing unlock in the XENMEM_acquire_resource error path. The RCU (Read, Copy, Update) mechanism is a synchronisation primitive. A buggy error path in the XENMEM_acquire_resource exits without releasing an RCU reference, which is conceptually similar to forgetting to unlock a spinlock. A buggy or malicious HVM stubdomain can cause an RCU reference to be leaked. This causes subsequent administration operations, (e.g., CPU offline) to livelock, resulting in a host Denial of Service. The buggy codepath has been present since Xen 4.12. Xen 4.14 and later are vulnerable to the DoS. The side effects are believed to be benign on Xen 4.12 and 4.13, but patches are provided nevertheless. The vulnerability can generally only be exploited by x86 HVM VMs, as these are generally the only type of VM that have a Qemu stubdomain. x86 PV and PVH domains, as well as ARM VMs, typically don't use a stubdomain. Only VMs using HVM stubdomains can exploit the vulnerability. VMs using PV stubdomains, or with emulators running in dom0, cannot exploit the vulnerability.

A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service.

In the Linux kernel 4.4 through 5.7.6, usbtest_disconnect in drivers/usb/misc/usbtest.c has a memory leak, aka CID-28ebeb8db770.

An issue was discovered in OpenEXR before 2.5.2. Invalid input could cause a use-after-free in DeepScanLineInputFile::DeepScanLineInputFile() in IlmImf/ImfDeepScanLineInputFile.cpp.

An unhandled exception in check_ignored() in apport/report.py can be exploited by a local attacker to cause a denial of service. If the mtime attribute is a string value in apport-ignore.xml, it will trigger an unhandled exception, resulting in a crash. Fixed in 2.20.1-0ubuntu2.24, 2.20.9-0ubuntu7.16, 2.20.11-0ubuntu27.6.

In SQLite before 3.32.3, select.c mishandles query-flattener optimization, leading to a multiSelectOrderBy heap overflow because of misuse of transitive properties for constant propagation.

An issue was discovered in OpenEXR before v2.5.2. Invalid chunkCount attributes could cause a heap buffer overflow in getChunkOffsetTableSize() in IlmImf/ImfMisc.cpp.

An integer underflow in dpdk versions before 18.11.10 and before 19.11.5 in the `move_desc` function can lead to large amounts of CPU cycles being eaten up in a long running loop. An attacker could cause `move_desc` to get stuck in a 4,294,967,295-count iteration loop. Depending on how `vhost_crypto` is being used this could prevent other VMs or network tasks from being serviced by the busy DPDK lcore for an extended period.

A memory out-of-bounds read flaw was found in the Linux kernel before 5.9-rc2 with the ext3/ext4 file system, in the way it accesses a directory with broken indexing. This flaw allows a local user to crash the system if the directory exists. The highest threat from this vulnerability is to system availability.

oss_write in audio/ossaudio.c in QEMU before 5.0.0 mishandles a buffer position.

An untrusted pointer dereference flaw was found in Perl-DBI < 1.643. A local attacker who is able to manipulate calls to dbd_db_login6_sv() could cause memory corruption, affecting the service's availability.

SQLite through 3.32.0 has an integer overflow in sqlite3_str_vappendf in printf.c.

exif_entry_get_value in exif-entry.c in libexif 0.6.21 has a divide-by-zero error.

sd_wp_addr in hw/sd/sd.c in QEMU 4.2.0 uses an unvalidated address, which leads to an out-of-bounds read during sdhci_write() operations. A guest OS user can crash the QEMU process.

ext/fts3/fts3_snippet.c in SQLite before 3.32.0 has a NULL pointer dereference via a crafted matchinfo() query.

In QEMU 5.0.0 and earlier, megasas_lookup_frame in hw/scsi/megasas.c has an out-of-bounds read via a crafted reply_queue_head field from a guest OS user.

In QEMU through 5.0.0, an integer overflow was found in the SM501 display driver implementation. This flaw occurs in the COPY_AREA macro while handling MMIO write operations through the sm501_2d_engine_write() callback. A local attacker could abuse this flaw to crash the QEMU process in sm501_2d_operation() in hw/display/sm501.c on the host, resulting in a denial of service.

There is a flaw in polkit which can allow an unprivileged user to cause polkit to crash, due to process file descriptor exhaustion. The highest threat from this vulnerability is to availability. NOTE: Polkit process outage duration is tied to the failing process being reaped and a new one being spawned

gss_mech_free in net/sunrpc/auth_gss/gss_mech_switch.c in the rpcsec_gss_krb5 implementation in the Linux kernel through 5.6.10 lacks certain domain_release calls, leading to a memory leak. Note: This was disputed with the assertion that the issue does not grant any access not already available. It is a problem that on unloading a specific kernel module some memory is leaked, but loading kernel modules is a privileged operation. A user could also write a kernel module to consume any amount of memory they like and load that replicating the effect of this bug

A NULL pointer dereference in sanei_epson_net_read in SANE Backends before 1.0.30 allows a malicious device connected to the same local network as the victim to cause a denial of service, aka GHSL-2020-075.

An issue was discovered in the Linux kernel before 5.6. svm_cpu_uninit in arch/x86/kvm/svm.c has a memory leak, aka CID-d80b64ff297e. NOTE: third parties dispute this issue because it's a one-time leak at the boot, the size is negligible, and it can't be triggered at will

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 for success, and a negative number for errors. Some misplaced brackets cause one error path to return 1 instead of a negative value. The grant table code in Linux treats this condition as success, and proceeds with incorrectly initialised state. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to map a grant, it hits the incorrect error path. This will crash a Linux based dom0 or backend domain.

In whoopsie, parse_report() from whoopsie.c allows a local attacker to cause a denial of service via a crafted file. The DoS is caused by resource exhaustion due to a memory leak. Fixed in 0.2.52.5ubuntu0.5, 0.2.62ubuntu0.5 and 0.2.69ubuntu0.1.

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of bad continuation handling in GNTTABOP_copy. Grant table operations are expected to return 0 for success, and a negative number for errors. The fix for CVE-2017-12135 introduced a path through grant copy handling where success may be returned to the caller without any action taken. In particular, the status fields of individual operations are left uninitialised, and may result in errant behaviour in the caller of GNTTABOP_copy. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to copy a grant, it hits the incorrect exit path. This returns success to the caller without doing anything, which may cause crashes or other incorrect behaviour.

Xen 4.5.x through 4.7.x on AMD systems without the NRip feature, when emulating instructions that generate software interrupts, allows local HVM guest OS users to cause a denial of service (guest crash) by leveraging IDT entry miscalculation.

The read_boot function in boot.c in dosfstools before 4.0 allows attackers to cause a denial of service (crash) via a crafted filesystem, which triggers a heap-based buffer overflow in the (1) read_fat function or an out-of-bounds heap read in (2) get_fat function.

fs/pnode.c in the Linux kernel before 4.5.4 does not properly traverse a mount propagation tree in a certain case involving a slave mount, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) via a crafted series of mount system calls.

Integer overflow in the VGA module in QEMU allows local guest OS users to cause a denial of service (out-of-bounds read and QEMU process crash) by editing VGA registers in VBE mode.

The ohci_bus_start function in the USB OHCI emulation support (hw/usb/hcd-ohci.c) in QEMU allows local guest OS administrators to cause a denial of service (NULL pointer dereference and QEMU process crash) via vectors related to multiple eof_timers.

VMX in Xen 4.6.x and earlier, when using an Intel or Cyrix CPU, allows local HVM guest users to cause a denial of service (guest crash) via vectors related to a non-canonical RIP.

The IPv4 implementation in the Linux kernel before 4.5.2 mishandles destruction of device objects, which allows guest OS users to cause a denial of service (host OS networking outage) by arranging for a large number of IP addresses.

The is_rndis function in the USB Net device emulator (hw/usb/dev-network.c) in QEMU before 2.5.1 does not properly validate USB configuration descriptor objects, which allows local guest OS administrators to cause a denial of service (NULL pointer dereference and QEMU process crash) via vectors involving a remote NDIS control message packet.

The QXL display driver in QXL Virtual GPU 0.1.0 allows local users to cause a denial of service (guest crash or hang) via a SPICE connection that prevents other threads from obtaining the qemu_mutex mutex. NOTE: some of these details are obtained from third party information.

Unspecified vulnerability in Oracle MySQL 5.6.28 and earlier and 5.7.10 and earlier allows local users to affect availability via vectors related to Security: Encryption.

VMFUNC emulation in Xen 4.6.x through 4.8.x on x86 systems using AMD virtualization extensions (aka SVM) allows local HVM guest OS users to cause a denial of service (hypervisor crash) by leveraging a missing NULL pointer check.

The set_fat function in fat.c in dosfstools before 4.0 might allow attackers to corrupt a FAT12 filesystem or cause a denial of service (invalid memory read and crash) by writing an odd number of clusters to the third to last entry on a FAT12 filesystem, which triggers an "off-by-two error."

The (1) libxl_set_memory_target function in tools/libxl/libxl.c and (2) libxl__build_post function in tools/libxl/libxl_dom.c in Xen 3.4.x through 4.6.x do not properly calculate the balloon size when using the populate-on-demand (PoD) system, which allows local HVM guest users to cause a denial of service (guest crash) via unspecified vectors related to "heavy memory pressure."

The xenmem_add_to_physmap_one function in arch/arm/mm.c in Xen 4.5.x, 4.4.x, and earlier does not limit the number of printk console messages when reporting a failure to retrieve a reference on a foreign page, which allows remote domains to cause a denial of service by leveraging permissions to map the memory of a foreign guest.

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.

A memory leak in the ccp_run_sha_cmd() function in drivers/crypto/ccp/ccp-ops.c in the Linux kernel through 5.3.9 allows attackers to cause a denial of service (memory consumption), aka CID-128c66429247.