hw: cpu: Incomplete cleanup in specific special register read operations (aka SRBDS update)

Incomplete cleanup in specific special register read operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Xenstore: Guests can create arbitrary number of nodes via transactions T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] In case a node has been created in a transaction and it is later deleted in the same transaction, the transaction will be terminated with an error. As this error is encountered only when handling the deleted node at transaction finalization, the transaction will have been performed partially and without updating the accounting information. This will enable a malicious guest to create arbitrary number of nodes.

virt: guest to host DoS by triggering an infinite loop in microcode via #DB exception

The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a denial of service (host OS panic or hang) by triggering many #DB (aka Debug) exceptions, related to svm.c.

xen: x86 software interrupt injection mis-handled (XSA-196)

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.

xen: x86 software interrupt injection mis-handled (XSA-196)

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 an incorrect choice for software interrupt delivery.

xen: x86 PV guests may be able to mask interrupts (XSA-202)

Xen through 4.8.x allows local x86 PV guest OS kernel administrators to cause a denial of service (host hang or crash) by modifying the instruction stream asynchronously while performing certain kernel operations.

xen: x86: missing NULL pointer check in VMFUNC emulation (XSA-203)

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.

xen: x86: Mishandling of SYSCALL singlestep during emulation (XSA-204)

Xen through 4.8.x allows local 64-bit x86 HVM guest OS users to gain privileges by leveraging mishandling of SYSCALL singlestep during emulation.

xen: x86 null segments not always treated as unusable (XSA-191)

The x86 emulator in Xen does not properly treat x86 NULL segments as unusable when accessing memory, which might allow local HVM guest users to gain privileges via vectors involving "unexpected" base/limit values.

xen: x86 PV guests may gain access to internally used pages (XSA-248)

An issue was discovered in Xen through 4.9.x allowing PV guest OS users to cause a denial of service (host OS crash) or gain host OS privileges in shadow mode by mapping a certain auxiliary page.

xen: improper bug check in x86 log-dirty handling (XSA-251)

An issue was discovered in Xen through 4.9.x allowing PV guest OS users to cause a denial of service (host OS crash) if shadow mode and log-dirty mode are in place, because of an incorrect assertion related to M2P.

xen: x86: broken check in memory_exchange() permits PV guest breakout (XSA-212)

An issue (known as XSA-212) was discovered in Xen, with fixes available for 4.8.x, 4.7.x, 4.6.x, 4.5.x, and 4.4.x. The earlier XSA-29 fix introduced an insufficient check on XENMEM_exchange input, allowing the caller to drive hypervisor memory accesses outside of the guest provided input/output arrays.

xen: broken x86 shadow mode refcount overflow check (XSA-249)

An issue was discovered in Xen through 4.9.x allowing guest OS users to cause a denial of service (host OS crash) or gain host OS privileges by leveraging an incorrect mask for reference-count overflow checking in shadow mode.

xen: improper x86 shadow mode refcount error handling (XSA-250)

An issue was discovered in Xen through 4.9.x allowing guest OS users to cause a denial of service (host OS crash) or gain host OS privileges by leveraging incorrect error handling for reference counting in shadow mode.

xen: Checks access permissions to MMIO ranges only after accessing them

Xen PV guest before Xen 4.3 checked access permissions to MMIO ranges only after accessing them, allowing host PCI device space memory reads, leading to information disclosure. This is an error in the get_user function. NOTE: the upstream Xen Project considers versions before 4.5.x to be EOL.

xen: x86: infinite loop due to missing PoD error checking (XSA-246)

An issue was discovered in Xen through 4.9.x allowing HVM guest OS users to cause a denial of service (infinite loop and host OS hang) by leveraging the mishandling of Populate on Demand (PoD) errors.

xen: pin count / page reference race in grant table code (XSA-236)

An issue was discovered in Xen through 4.9.x. Grant copying code made an implication that any grant pin would be accompanied by a suitable page reference. Other portions of code, however, did not match up with that assumption. When such a grant copy operation is being done on a grant of a dying domain, the assumption turns out wrong. A malicious guest administrator can cause hypervisor memory corruption, most likely resulting in host crash and a Denial of Service. Privilege escalation and information leaks cannot be ruled out.

xen: Missing p2m error checking in PoD code (XSA-247)

An issue was discovered in Xen through 4.9.x allowing HVM guest OS users to gain privileges on the host OS, obtain sensitive information, or cause a denial of service (BUG and host OS crash) by leveraging the mishandling of Populate on Demand (PoD) Physical-to-Machine (P2M) errors.

xen: Unlimited recursion in linear pagetable de-typing (XSA-240)

An issue was discovered in Xen through 4.9.x allowing x86 PV guest OS users to cause a denial of service (unbounded recursion, stack consumption, and hypervisor crash) or possibly gain privileges via crafted page-table stacking.

xen: add-to-physmap error paths fail to release lock on ARM

An issue was discovered in Xen 4.4.x through 4.9.x allowing ARM guest OS users to cause a denial of service (prevent physical CPU usage) because of lock mishandling upon detection of an add-to-physmap error.