Xen Project VCPUOP_initialise DoS (XSA-296)

According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by a denial of service vulnerability due to poor handling of an invalid format string in 'hypercallcreatecontinuation'. This function can be reached via a long-running 'VCPUOPinitialise'...

CVE-2019-18425

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

CVE-2019-18425

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

CVE-2019-18420

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOPinitialise hypercall. hypercallcreatecontinuation is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format...

CVE-2019-18420

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOPinitialise hypercall. hypercallcreatecontinuation is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format...

CVE-2019-18420

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOPinitialise hypercall. hypercallcreatecontinuation is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format...

Race condition

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations. There are issues with restartable PV type change operations. To avoid using shadow pagetables for PV guests, Xen...

Code injection

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

Format string

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOPinitialise hypercall. hypercallcreatecontinuation is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format...

CVE-2019-18425

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

CVE-2019-18421

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations. There are issues with restartable PV type change operations. To avoid using shadow pagetables for PV guests, Xen...

CVE-2019-18425

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

CVE-2019-18425

An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performe...

CVE-2019-18425

CVE-2019-18425 affects Xen across 3.2+ and enables privilege escalation in 32-bit PV guests due to missing descriptor table limit checks in x86 PV emulation. The vulnerability is limited to 32-bit PV guest user mode; HVM/PVH/64-bit PV guests and ARM are not affected. Exploitation would let a gues...

CVE-2019-18421

CVE-2019-18421 affects the Xen hypervisor on x86 PV guests. Root cause: restartable PV type changes with recursive pagetable promotions/demotions contain races that can lead to incorrect type counts, enabling a PV guest to gain host privileges. Impact: local privilege escalation to host OS on all...

CVE-2019-18421

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations. There are issues with restartable PV type change operations. To avoid using shadow pagetables for PV guests, Xen...

CVE-2019-18420

An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to cause a denial of service via a VCPUOPinitialise hypercall. hypercallcreatecontinuation is a variadic function which uses a printf-like format string to interpret its parameters. Error handling for a bad format...

CVE-2019-18420

CVE-2019-18420 affects the Xen hypervisor (x86 PV guests). A bug in VCPUOP_initialise handling, where hypercall_create_continuation() uses a printf-like format string and BUG() for bad characters, can crash the hypervisor if a guest causes a long continuation, enabling Denial of Service. Vulnerab...

missing descriptor table limit checking in x86 PV emulation

ISSUE DESCRIPTION When emulating certain PV guest operations, descriptor table accesses are performed by the emulating code. Such accesses should respect the guest specified limits, unless otherwise guaranteed to fail in such a case. Without this, emulation of 32-bit guest user mode calls through...

Issues with restartable PV type change operations

ISSUE DESCRIPTION To avoid using shadow pagetables for PV guests, Xen exposes the actual hardware pagetables to the guest. In order to prevent the guest from modifying these page tables directly, Xen keeps track of how pages are used using a type system; pages must be "promoted" before being used...