Xen vulnerabilities, page 3
477 vulnerabilities
Known vulnerabilities in Xen products, newest first, with CVSS severity, EPSS, KEV listings and ransomware use, across 8 products.
RoutineCVE-2023-46837xen +3 morearm32: The cache may not be properly cleaned/invalidated (take two)Arm provides multiple helpers to clean & invalidate the cache
for a given region. This is, for instance, used when allocating
guest memory to ensure any writes (such as the ones during scrubbing)
have reached memory before handing over the page to a guest.
Unfortunately, the arithmetics in the helpers can overflow and would
then result to skip the cache cleaning/invalidation. Therefore there
is no guarantee when all the writes will reach the memory.
This undefined behavior was meant to be addressed by XSA-437, but the
approach was not sufficient.CVSS3.3LowEPSS0.24%RoutineCVE-2023-34328xen +3 morex86/AMD: Debug Mask handling[This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]
AMD CPUs since ~2014 have extensions to normal x86 debugging functionality.
Xen supports guests using these extensions.
Unfortunately there are errors in Xen's handling of the guest state, leading
to denials of service.
1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of
a previous vCPUs debug mask state.
2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT.
This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock
up the CPU entirely.CVSS5.5MediumEPSS0.24%RoutineCVE-2023-34327xen +3 morex86/AMD: Debug Mask handling[This CNA information record relates to multiple CVEs; the
text explains which aspects/vulnerabilities correspond to which CVE.]
AMD CPUs since ~2014 have extensions to normal x86 debugging functionality.
Xen supports guests using these extensions.
Unfortunately there are errors in Xen's handling of the guest state, leading
to denials of service.
1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of
a previous vCPUs debug mask state.
2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT.
This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock
up the CPU entirely.CVSS5.5MediumEPSS0.24%RoutineCVE-2023-34324linux · linux_kernel +116 morePossible deadlock in Linux kernel event handlingClosing of an event channel in the Linux kernel can result in a deadlock.
This happens when the close is being performed in parallel to an unrelated
Xen console action and the handling of a Xen console interrupt in an
unprivileged guest.
The closing of an event channel is e.g. triggered by removal of a
paravirtual device on the other side. As this action will cause console
messages to be issued on the other side quite often, the chance of
triggering the deadlock is not neglectable.
Note that 32-bit Arm-guests are not affected, as the 32-bit Linux kernel
on Arm doesn't use queued-RW-locks, which are required to trigger the
issue (on Arm32 a waiting writer doesn't block further readers to get
the lock).CVSS4.9MediumEPSS1.15%RoutineCVE-2023-34323xen +3 morexenstored: A transaction conflict can crash C XenstoredWhen a transaction is committed, C Xenstored will first check
the quota is correct before attempting to commit any nodes. It would
be possible that accounting is temporarily negative if a node has
been removed outside of the transaction.
Unfortunately, some versions of C Xenstored are assuming that the
quota cannot be negative and are using assert() to confirm it. This
will lead to C Xenstored crash when tools are built without -DNDEBUG
(this is the default).CVSS5.5MediumEPSS0.24%RoutineCVE-2023-34322xen +3 moretop-level shadow reference dropped too early for 64-bit PV guestsFor migration as well as to work around kernels unaware of L1TF (see
XSA-273), PV guests may be run in shadow paging mode. Since Xen itself
needs to be mapped when PV guests run, Xen and shadowed PV guests run
directly the respective shadow page tables. For 64-bit PV guests this
means running on the shadow of the guest root page table.
In the course of dealing with shortage of memory in the shadow pool
associated with a domain, shadows of page tables may be torn down. This
tearing down may include the shadow root page table that the CPU in
question is presently running on. While a precaution exists to
supposedly prevent the tearing down of the underlying live page table,
the time window covered by that precaution isn't large enough.CVSS7.8HighEPSS0.22%RoutineCVE-2023-34321xen +3 morearm32: The cache may not be properly cleaned/invalidatedArm provides multiple helpers to clean & invalidate the cache
for a given region. This is, for instance, used when allocating
guest memory to ensure any writes (such as the ones during scrubbing)
have reached memory before handing over the page to a guest.
Unfortunately, the arithmetics in the helpers can overflow and would
then result to skip the cache cleaning/invalidation. Therefore there
is no guarantee when all the writes will reach the memory.CVSS3.3LowEPSS0.25%RoutineCVE-2023-4949free software foundation · grub-legacy +3 moreMemory Corruption Vulnerability in Grub-Legacy's XFS ImplementationAn attacker with local access to a system (either through a disk or external drive) can present a modified XFS partition to grub-legacy in such a way to exploit a memory corruption in grub’s XFS file system implementation.CVSS8.1HighEPSS0.24%RoutineCVE-2023-34319debian · debian_linux +108 moreLinux: buffer overrun in netback due to unusual packetThe fix for XSA-423 added logic to Linux'es netback driver to deal with
a frontend splitting a packet in a way such that not all of the headers
would come in one piece. Unfortunately the logic introduced there
didn't account for the extreme case of the entire packet being split
into as many pieces as permitted by the protocol, yet still being
smaller than the area that's specially dealt with to keep all (possible)
headers together. Such an unusual packet would therefore trigger a
buffer overrun in the driver.CVSS7.8HighEPSS0.29%RoutineCVE-2022-40982debian · debian_linux +641 moredebian debian_linuxInformation exposure through microarchitectural state after transient execution in certain vector execution units for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.CVSS6.5MediumEPSS3.05%RoutineCVE-2023-20588amd · athlon™ 3000 series processors with radeon™ graphics +159 moreSpeculative LeaksA division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality.CVSS5.5MediumEPSS11.15%RoutineCVE-2023-20593amd · 2nd gen amd epyc™ processors +259 moreamd 2nd gen amd epyc™ processorsAn issue in “Zen 2” CPUs, under specific microarchitectural circumstances, may allow an attacker to potentially access sensitive information.CVSS5.5MediumEPSS5.07%PrioritiseCVE-2022-4949https://adsanityplugin.com/ · adsanity +3 moreAdSanity < 1.8.2 - Authenticated Arbitrary File UploadThe AdSanity plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'ajax_upload' function in versions up to, and including, 1.8.1. This makes it possible for authenticated attackers with Contributor+ level privileges to upload arbitrary files on the affected sites server which makes remote code execution possible.CVSS8.8HighEPSS2.18%RoutineCVE-2022-42336xen +4 morexen xenMishandling of guest SSBD selection on AMD hardware The current logic to set SSBD on AMD Family 17h and Hygon Family 18h processors requires that the setting of SSBD is coordinated at a core level, as the setting is shared between threads. Logic was introduced to keep track of how many threads require SSBD active in order to coordinate it, such logic relies on using a per-core counter of threads that have SSBD active. When running on the mentioned hardware, it's possible for a guest to under or overflow the thread counter, because each write to VIRT_SPEC_CTRL.SSBD by the guest gets propagated to the helper that does the per-core active accounting. Underflowing the counter causes the value to get saturated, and thus attempts for guests running on the same core to set SSBD won't have effect because the hypervisor assumes it's already active.CVSS3.3LowEPSS0.27%RoutineCVE-2022-42335fedoraproject · fedora +5 morefedoraproject fedorax86 shadow paging arbitrary pointer dereference In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Due to too lax a check in one of the hypervisor routines used for shadow page handling it is possible for a guest with a PCI device passed through to cause the hypervisor to access an arbitrary pointer partially under guest control.CVSS7.8HighEPSS0.26%RoutineCVE-2022-42334debian · debian_linux +5 moredebian debian_linuxx86/HVM pinned cache attributes mis-handling T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To allow cachability control for HVM guests with passed through devices, an interface exists to explicitly override defaults which would otherwise be put in place. While not exposed to the affected guests themselves, the interface specifically exists for domains controlling such guests. This interface may therefore be used by not fully privileged entities, e.g. qemu running deprivileged in Dom0 or qemu running in a so called stub-domain. With this exposure it is an issue that - the number of the such controlled regions was unbounded (CVE-2022-42333), - installation and removal of such regions was not properly serialized (CVE-2022-42334).CVSS6.5MediumEPSS0.27%PrioritiseCVE-2022-42333debian · debian_linux +5 moredebian debian_linuxx86/HVM pinned cache attributes mis-handling T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] To allow cachability control for HVM guests with passed through devices, an interface exists to explicitly override defaults which would otherwise be put in place. While not exposed to the affected guests themselves, the interface specifically exists for domains controlling such guests. This interface may therefore be used by not fully privileged entities, e.g. qemu running deprivileged in Dom0 or qemu running in a so called stub-domain. With this exposure it is an issue that - the number of the such controlled regions was unbounded (CVE-2022-42333), - installation and removal of such regions was not properly serialized (CVE-2022-42334).CVSS8.6HighEPSS1.19%RoutineCVE-2022-42332debian · debian_linux +5 moredebian debian_linuxx86 shadow plus log-dirty mode use-after-free In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Shadow mode maintains a pool of memory used for both shadow page tables as well as auxiliary data structures. To migrate or snapshot guests, Xen additionally runs them in so called log-dirty mode. The data structures needed by the log-dirty tracking are part of aformentioned auxiliary data. In order to keep error handling efforts within reasonable bounds, for operations which may require memory allocations shadow mode logic ensures up front that enough memory is available for the worst case requirements. Unfortunately, while page table memory is properly accounted for on the code path requiring the potential establishing of new shadows, demands by the log-dirty infrastructure were not taken into consideration. As a result, just established shadow page tables could be freed again immediately, while other code is still accessing them on the assumption that they would remain allocated.CVSS7.8HighEPSS0.27%RoutineCVE-2022-42331fedoraproject · fedora +4 morefedoraproject fedorax86: speculative vulnerability in 32bit SYSCALL path Due to an oversight in the very original Spectre/Meltdown security work (XSA-254), one entrypath performs its speculation-safety actions too late. In some configurations, there is an unprotected RET instruction which can be attacked with a variety of speculative attacks.CVSS5.5MediumEPSS0.28%PrioritiseCVE-2022-42330xen +4 morexen xenGuests can cause Xenstore crash via soft reset When a guest issues a "Soft Reset" (e.g. for performing a kexec) the libxl based Xen toolstack will normally perform a XS_RELEASE Xenstore operation. Due to a bug in xenstored this can result in a crash of xenstored. Any other use of XS_RELEASE will have the same impact.CVSS7.5HighEPSS1.36%