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.

Memory leak in the serial_exit_core function in hw/char/serial.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.

Memory leak in the megasas_handle_dcmd function in hw/scsi/megasas.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (host memory consumption) via MegaRAID Firmware Interface (MFI) commands with the sglist size set to a value over 2 Gb.

A race condition was found in util-linux before 2.32.1 in the way su handled the management of child processes. A local authenticated attacker could use this flaw to kill other processes with root privileges under specific conditions.

Integer overflow in the macro ROUND_UP (n, d) in Quick Emulator (Qemu) allows a user to cause a denial of service (Qemu process crash).

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.

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.

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.

An issue was discovered in the Linux kernel through 5.11.3, as used with Xen PV. A certain part of the netback driver lacks necessary treatment of errors such as failed memory allocations (as a result of changes to the handling of grant mapping errors). A host OS denial of service may occur during misbehavior of a networking frontend driver. NOTE: this issue exists because of an incomplete fix for CVE-2021-26931.

Memory leak in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local privileged guest OS users to cause a denial of service (host memory consumption and possibly QEMU process crash) by leveraging a missing cleanup operation in FileOperations.

An issue was discovered in Xen through 4.14.x. Nodes in xenstore have an ownership. In oxenstored, a owner could give a node away. However, node ownership has quota implications. Any guest can run another guest out of quota, or create an unbounded number of nodes owned by dom0, thus running xenstored out of memory A malicious guest administrator can cause a denial of service against a specific guest or against the whole host. 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 4.14.x. Xenstored and guests communicate via a shared memory page using a specific protocol. When a guest violates this protocol, xenstored will drop the connection to that guest. Unfortunately, this is done by just removing the guest from xenstored's internal management, resulting in the same actions as if the guest had been destroyed, including sending an @releaseDomain event. @releaseDomain events do not say that the guest has been removed. All watchers of this event must look at the states of all guests to find the guest that has been removed. When an @releaseDomain is generated due to a domain xenstored protocol violation, because the guest is still running, the watchers will not react. Later, when the guest is actually destroyed, xenstored will no longer have it stored in its internal data base, so no further @releaseDomain event will be sent. This can lead to a zombie domain; memory mappings of that guest's memory will not be removed, due to the missing event. This zombie domain will be cleaned up only after another domain is destroyed, as that will trigger another @releaseDomain event. If the device model of the guest that violated the Xenstore protocol is running in a stub-domain, a use-after-free case could happen in xenstored, after having removed the guest from its internal data base, possibly resulting in a crash of xenstored. A malicious guest can block resources of the host for a period after its own death. Guests with a stub domain device model can eventually crash xenstored, resulting in a more serious denial of service (the prevention of any further domain management operations). Only the C variant of Xenstore is affected; the Ocaml variant is not affected. Only HVM guests with a stubdom device model can cause a serious DoS.

Quick Emulator (Qemu) built with the USB EHCI Emulation support is vulnerable to a memory leakage issue. It could occur while processing packet data in 'ehci_init_transfer'. A guest user/process could use this issue to leak host memory, resulting in DoS for a host.

Quick Emulator (Qemu) built with the USB redirector usb-guest support is vulnerable to a memory leakage flaw. It could occur while destroying the USB redirector in 'usbredir_handle_destroy'. A guest user/process could use this issue to leak host memory, resulting in DoS for a host.

There is a NULL pointer dereference in the AnnotPath::getCoordsLength function in Annot.h in an Ubuntu package for Poppler 0.24.5. A crafted input will lead to a remote denial of service attack. Later Ubuntu packages such as for Poppler 0.41.0 are not affected.

A Null Pointer Deference issue exists in Academy Software Foundation OpenEXR 2.3.0 in generatePreview in makePreview.cpp that can cause a denial of service via a crafted EXR file.

The Linux kernel before version 4.11 is vulnerable to a NULL pointer dereference in fs/cifs/cifsencrypt.c:setup_ntlmv2_rsp() that allows an attacker controlling a CIFS server to kernel panic a client that has this server mounted, because an empty TargetInfo field in an NTLMSSP setup negotiation response is mishandled during session recovery.

In QEMU 4.2.0, a MemoryRegionOps object may lack read/write callback methods, leading to a NULL pointer dereference.

Insufficient data validation in media in Google Chrome prior to 85.0.4183.121 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.

All versions of Samba from 4.0.0 onwards are vulnerable to a denial of service attack when the RPC spoolss service is configured to be run as an external daemon. Missing input sanitization checks on some of the input parameters to spoolss RPC calls could cause the print spooler service to crash.

An issue was discovered in PHP before 5.6.36, 7.0.x before 7.0.30, 7.1.x before 7.1.17, and 7.2.x before 7.2.5. ext/ldap/ldap.c allows remote LDAP servers to cause a denial of service (NULL pointer dereference and application crash) because of mishandling of the ldap_get_dn return value.

nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client. This vulnerability appears to have been fixed in >= 1.31.1.

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.

The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.

A NULL pointer dereference exists in curl 7.21.0 to and including curl 7.58.0 in the LDAP code that allows an attacker to cause a denial of service

A NULL Pointer Dereference of CWE-476 exists in quassel version 0.12.4 in the quasselcore void CoreAuthHandler::handle(const Login &msg) coreauthhandler.cpp line 235 that allows an attacker to cause a denial of service.

The econet_sendmsg function in net/econet/af_econet.c in the Linux kernel before 2.6.36.2, when an econet address is configured, allows local users to cause a denial of service (NULL pointer dereference and OOPS) via a sendmsg call that specifies a NULL value for the remote address field.

Null pointer dereference when viewing a specially crafted email in Mutt >1.5.2 <2.2.12

A null pointer dereference vulnerability in devices/vector/gdevtxtw.c and psi/zbfont.c of Artifex Software GhostScript v9.50 allows a remote attacker to cause a denial of service via a crafted postscript file. This is fixed in v9.51.

A null pointer dereference vulnerability in devices/gdevtsep.c of Artifex Software GhostScript v9.50 allows a remote attacker to cause a denial of service via a crafted postscript file. This is fixed in v9.51.

The gfs2_dirent_find_space function in fs/gfs2/dir.c in the Linux kernel before 2.6.35 uses an incorrect size value in calculations associated with sentinel directory entries, which allows local users to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact by renaming a file in a GFS2 filesystem, related to the gfs2_rename function in fs/gfs2/ops_inode.c.

util/outputtxt.c in libming 0.4.8 mishandles memory allocation. A crafted input will lead to a remote denial of service (NULL pointer dereference) attack.

An issue was discovered in Tor before 0.2.9.15, 0.3.1.x before 0.3.1.10, and 0.3.2.x before 0.3.2.10. The directory-authority protocol-list subprotocol implementation allows remote attackers to cause a denial of service (NULL pointer dereference and directory-authority crash) via a misformatted relay descriptor that is mishandled during voting.

The readEncUInt30 function in util/read.c in libming 0.4.8 mishandles memory allocation. A crafted input will lead to a remote denial of service (NULL pointer dereference) attack against parser.c.

In GNOME evolution-data-server before 3.35.91, a malicious server can crash the mail client with a NULL pointer dereference by sending an invalid (e.g., minimal) CAPABILITY line on a connection attempt. This is related to imapx_free_capability and imapx_connect_to_server.

The Gfx::getPos function in the PDF parser in xpdf before 3.02pl5, poppler 0.8.7 and possibly other versions up to 0.15.1, CUPS, kdegraphics, and possibly other products allows context-dependent attackers to cause a denial of service (crash) via unknown vectors that trigger an uninitialized pointer dereference.

A flaw was found in the Linux kernel’s KVM when attempting to set a SynIC IRQ. This issue makes it possible for a misbehaving VMM to write to SYNIC/STIMER MSRs, causing a NULL pointer dereference. This flaw allows an unprivileged local attacker on the host to issue specific ioctl calls, causing a kernel oops condition that results in a denial of service.

Integer signedness error in the pkt_find_dev_from_minor function in drivers/block/pktcdvd.c in the Linux kernel before 2.6.36-rc6 allows local users to obtain sensitive information from kernel memory or cause a denial of service (invalid pointer dereference and system crash) via a crafted index value in a PKT_CTRL_CMD_STATUS ioctl call.

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.

Transmit requests in Xen's virtual network protocol can consist of multiple parts. While not really useful, except for the initial part any of them may be of zero length, i.e. carry no data at all. Besides a certain initial portion of the to be transferred data, these parts are directly translated into what Linux calls SKB fragments. Such converted request parts can, when for a particular SKB they are all of length zero, lead to a de-reference of NULL in core networking code.

libjbig2dec.a in Artifex jbig2dec 0.13, as used in MuPDF and Ghostscript, has a NULL pointer dereference in the jbig2_huffman_get function in jbig2_huffman.c. For example, the jbig2dec utility will crash (segmentation fault) when parsing an invalid file.

QEMU (aka Quick Emulator), when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, allows local guest OS privileged users to cause a denial of service (NULL pointer dereference and QEMU process crash) via vectors involving megasas command processing.

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, remote attackers can cause a denial of service (NULL pointer dereference and application crash) against directory authorities via a malformed descriptor, aka TROVE-2017-010.

In Irssi before 1.0.3, when receiving a DCC message without source nick/host, it attempts to dereference a NULL pointer. Thus, remote IRC servers can cause a crash.

The kg_accept_krb5 function in krb5/accept_sec_context.c in the GSS-API library in MIT Kerberos 5 (aka krb5) through 1.7.1 and 1.8 before 1.8.2, as used in kadmind and other applications, does not properly check for invalid GSS-API tokens, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an AP-REQ message in which the authenticator's checksum field is missing.

An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.

xpdf allows remote attackers to cause a denial of service (NULL pointer dereference and crash) in the way it processes JBIG2 PDF stream objects.

Race condition in the tty_fasync function in drivers/char/tty_io.c in the Linux kernel before 2.6.32.6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via unknown vectors, related to the put_tty_queue and __f_setown functions. NOTE: the vulnerability was addressed in a different way in 2.6.32.9.

A null pointer dereference flaw was found in samba's Winbind service in versions before 4.11.15, before 4.12.9 and before 4.13.1. A local user could use this flaw to crash the winbind service causing denial of service.

address_space_map in exec.c in QEMU 4.2.0 can trigger a NULL pointer dereference related to BounceBuffer.