A flaw was found in the QEMU virtual crypto device while handling data encryption/decryption requests in virtio_crypto_handle_sym_req. There is no check for the value of `src_len` and `dst_len` in virtio_crypto_sym_op_helper, potentially leading to a heap buffer overflow when the two values differ.

The ahci_commit_buf function in ide/ahci.c in QEMU allows attackers to cause a denial of service (NULL dereference) when the command header 'ad->cur_cmd' is null.

P2M pool freeing may take excessively long The P2M pool backing second level address translation for guests may be of significant size. Therefore its freeing may take more time than is reasonable without intermediate preemption checks. Such checking for the need to preempt was so far missing.

drivers/firmware/dell_rbu.c in the Linux kernel before 2.6.27.13, and 2.6.28.x before 2.6.28.2, allows local users to cause a denial of service (system crash) via a read system call that specifies zero bytes from the (1) image_type or (2) packet_size file in /sys/devices/platform/dell_rbu/.

fs/splice.c in the splice subsystem in the Linux kernel before 2.6.22.2 does not properly handle a failure of the add_to_page_cache_lru function, and subsequently attempts to unlock a page that was not locked, which allows local users to cause a denial of service (kernel BUG and system crash), as demonstrated by the fio I/O tool.

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

An issue was discovered in Xen 4.8.x through 4.10.x allowing x86 PVH guest OS users to cause a denial of service (NULL pointer dereference and hypervisor crash) by leveraging the mishandling of configurations that lack a Local APIC.

A NULL pointer dereference was found in the net/rds/rdma.c __rds_rdma_map() function in the Linux kernel before 4.14.7 allowing local attackers to cause a system panic and a denial-of-service, related to RDS_GET_MR and RDS_GET_MR_FOR_DEST.

An issue was discovered in Xen through 4.10.x allowing x86 PV guest OS users to cause a denial of service (host OS CPU hang) via non-preemptable L3/L4 pagetable freeing.

The resv_map_release function in mm/hugetlb.c in the Linux kernel through 4.15.7 allows local users to cause a denial of service (BUG) via a crafted application that makes mmap system calls and has a large pgoff argument to the remap_file_pages system call.

An issue was discovered in the Linux kernel before 5.2.1. There is a use-after-free caused by a malicious USB device in the drivers/net/wireless/intersil/p54/p54usb.c driver.

In the Linux Kernel before version 4.15.8, 4.14.25, 4.9.87, 4.4.121, 4.1.51, and 3.2.102, an error in the "_sctp_make_chunk()" function (net/sctp/sm_make_chunk.c) when handling SCTP packets length can be exploited to cause a kernel crash.

In the Linux kernel through 4.14.13, the rds_cmsg_atomic function in net/rds/rdma.c mishandles cases where page pinning fails or an invalid address is supplied, leading to an rds_atomic_free_op NULL pointer dereference.

There are use-after-free vulnerabilities caused by timer handler in net/rose/rose_timer.c of linux that allow attackers to crash linux kernel without any privileges.

An issue was discovered in Xen through 4.11.x on Intel x86 platforms allowing guest OS users to cause a denial of service (host OS hang) because Xen does not work around Intel's mishandling of certain HLE transactions associated with the KACQUIRE instruction prefix.

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.

On May 4, 2022, the following vulnerability in the ClamAV scanning library versions 0.103.5 and earlier and 0.104.2 and earlier was disclosed: A vulnerability in Clam AntiVirus (ClamAV) versions 0.103.4, 0.103.5, 0.104.1, and 0.104.2 could allow an authenticated, local attacker to cause a denial of service condition on an affected device. For a description of this vulnerability, see the ClamAV blog.

An issue was discovered in Xen through 4.11.x. ARM never properly implemented grant table v2, either in the hypervisor or in Linux. Unfortunately, an ARM guest can still request v2 grant tables; they will simply not be properly set up, resulting in subsequent grant-related hypercalls hitting BUG() checks. An unprivileged guest can cause a BUG() check in the hypervisor, resulting in a denial-of-service (crash).

A NULL pointer dereference flaw was found in the Linux kernel’s X.25 set of standardized network protocols functionality in the way a user terminates their session using a simulated Ethernet card and continued usage of this connection. This flaw allows a local user to crash the system.

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.

A flaw null pointer dereference in the Linux kernel UDF file system functionality was found in the way user triggers udf_file_write_iter function for the malicious UDF image. A local user could use this flaw to crash the system. Actual from Linux kernel 4.2-rc1 till 5.17-rc2.

An issue was discovered in Xen through 4.10.x allowing x86 PV guest OS users to cause a denial of service (out-of-bounds zero write and hypervisor crash) via unexpected INT 80 processing, because of an incorrect fix for CVE-2017-5754.

A flaw was found in the Linux kernel's ext4 filesystem. A local user can cause an out-of-bounds write in jbd2_journal_dirty_metadata(), a denial of service, and a system crash by mounting and operating on a crafted ext4 filesystem image.

A flaw was found in the Linux kernel's ext4 filesystem. A local user can cause an out-of-bound write in in fs/jbd2/transaction.c code, a denial of service, and a system crash by unmounting 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.

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.

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.

The cdrom_ioctl_media_changed function in drivers/cdrom/cdrom.c in the Linux kernel before 4.16.6 allows local attackers to use a incorrect bounds check in the CDROM driver CDROM_MEDIA_CHANGED ioctl to read out kernel memory.

The xfs_bmap_extents_to_btree function in fs/xfs/libxfs/xfs_bmap.c in the Linux kernel through 4.16.3 allows local users to cause a denial of service (xfs_bmapi_write NULL pointer dereference) via a crafted xfs image.

The Linux Kernel version 3.18 contains a dangerous feature vulnerability in modify_user_hw_breakpoint() that can result in crash and possibly memory corruption. This attack appear to be exploitable via local code execution and the ability to use ptrace. This vulnerability appears to have been fixed in git commit f67b15037a7a50c57f72e69a6d59941ad90a0f0f.

hw/scsi/vmw_pvscsi.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (infinite loop and CPU consumption) via the message ring page count.

Memory leak in the v9fs_list_xattr function in hw/9pfs/9p-xattr.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (memory consumption) via vectors involving the orig_value variable.

Memory leak in the keyboard input event handlers support in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (host memory consumption) by rapidly generating large keyboard events.

The ohci_service_ed_list function in hw/usb/hcd-ohci.c in QEMU (aka Quick Emulator) before 2.9.0 allows local guest OS users to cause a denial of service (infinite loop) via vectors involving the number of link endpoint list descriptors, a different vulnerability than CVE-2017-9330.

The sdhci_sdma_transfer_multi_blocks function in hw/sd/sdhci.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (out-of-bounds heap access and crash) or execute arbitrary code on the QEMU host via vectors involving the data transfer length.

An integer overflow was found in the QEMU implementation of VMWare's paravirtual RDMA device in versions prior to 6.1.0. The issue occurs while handling a "PVRDMA_REG_DSRHIGH" write from the guest due to improper input validation. This flaw allows a privileged guest user to make QEMU allocate a large amount of memory, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

A stack overflow vulnerability was found in the Intel HD Audio device (intel-hda) of QEMU. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability. This flaw affects QEMU versions prior to 7.0.0.

A flaw was found in the Linux kernel's handling of clearing SELinux attributes on /proc/pid/attr files before 4.9.10. An empty (null) write to this file can crash the system by causing the system to attempt to access unmapped kernel memory.

fs/f2fs/segment.c in the Linux kernel before 4.13 allows local users to cause a denial of service (NULL pointer dereference and panic) by using a noflush_merge option that triggers a NULL value for a flush_cmd_control data structure.

basic/unit-name.c in systemd prior to 246.15, 247.8, 248.5, and 249.1 has a Memory Allocation with an Excessive Size Value (involving strdupa and alloca for a pathname controlled by a local attacker) that results in an operating system crash.

kernel/bpf/verifier.c in the Linux kernel through 4.14.8 ignores unreachable code, even though it would still be processed by JIT compilers. This behavior, also considered an improper branch-pruning logic issue, could possibly be used by local users for denial of service.

The __get_data_block function in fs/f2fs/data.c in the Linux kernel before 4.11 allows local users to cause a denial of service (integer overflow and loop) via crafted use of the open and fallocate system calls with an FS_IOC_FIEMAP ioctl.

The Virtio Vring implementation in QEMU allows local OS guest users to cause a denial of service (divide-by-zero error and QEMU process crash) by unsetting vring alignment while updating Virtio rings.

Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as "driver domains". Running PV backends in driver domains has one primary security advantage: if a driver domain gets compromised, it doesn't have the privileges to take over the system. However, a malicious driver domain could try to attack other guests via sending events at a high frequency leading to a Denial of Service in the guest due to trying to service interrupts for elongated amounts of time. There are three affected backends: * blkfront patch 1, CVE-2021-28711 * netfront patch 2, CVE-2021-28712 * hvc_xen (console) patch 3, CVE-2021-28713

Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default). Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time. (CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. (CVE-2021-28714)

A certain backport in the TCP Fast Open implementation for the Linux kernel before 3.18 does not properly maintain a count value, which allow local users to cause a denial of service (system crash) via the Fast Open feature, as demonstrated by visiting the chrome://flags/#enable-tcp-fast-open URL when using certain 3.10.x through 3.16.x kernel builds, including longterm-maintenance releases and ckt (aka Canonical Kernel Team) builds.

Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default). Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time. (CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. (CVE-2021-28714)

Guests can trigger NIC interface reset/abort/crash via netback It is possible for a guest to trigger a NIC interface reset/abort/crash in a Linux based network backend by sending certain kinds of packets. It appears to be an (unwritten?) assumption in the rest of the Linux network stack that packet protocol headers are all contained within the linear section of the SKB and some NICs behave badly if this is not the case. This has been reported to occur with Cisco (enic) and Broadcom NetXtrem II BCM5780 (bnx2x) though it may be an issue with other NICs/drivers as well. In case the frontend is sending requests with split headers, netback will forward those violating above mentioned assumption to the networking core, resulting in said misbehavior.

A flaw was found in the QEMU implementation of VMWare's paravirtual RDMA device in versions prior to 6.1.0. The issue occurs while handling a "PVRDMA_REG_DSRHIGH" write from the guest and may result in a crash of QEMU or cause undefined behavior due to the access of an uninitialized pointer. The highest threat from this vulnerability is to system availability.