UBUNTU-CVE-2020-25600

An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm either bitness ones. 32-bit x86 domain...

UBUNTU-CVE-2020-25601

An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchnreset / evtchndestroy. In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these when resetting all event channels or when cleaning...

UBUNTU-CVE-2020-25603

An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier e.g., smp...

CVE-2020-25603

An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier e.g., smp...

CVE-2020-25603

CVE-2020-25603 affects Xen up to 4.14.x, where missing memory barriers in event-channel access/allocation allow lockless manipulation of event-channel state. A malicious guest could crash the hypervisor, causing a Denial of Service, with potential information leaks or privilege escalation. Public...

CVE-2020-25603

An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier e.g., smp...

CVE-2020-25601

CVE-2020-25601 (Xen) : A lack of preemption in evtchn_reset() and evtchn_destroy() inside the FIFO event channel model can cause a guest with many active event channels to stall the hypervisor, enabling a local attacker (malicious or buggy guest kernel) to mount a Denial of Service affecting the ...

CVE-2020-25601

An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchnreset / evtchndestroy. In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these when resetting all event channels or when cleaning...

CVE-2020-25600

An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm either bitness ones. 32-bit x86 domain...

CVE-2020-25600

An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm either bitness ones. 32-bit x86 domain...

CVE-2020-25600

The connected XSA-342 advisory provides concrete details for CVE-2020-25600: Xen 2-level event channel model mismanages the per-guest limit, causing 32-bit x86 domains (including Domain 0) to observe successful allocations that should fail, risking corruption of the shared info structure and enab...

CVE-2020-25597

CVE-2020-25597 concerns Xen’s event-channel validity check. The issue arises from mishandling of the constraint that an already valid event channel may become invalid, which can occur when resetting event channels. A malicious, unprivileged guest could trigger a crash of Xen, causing a host-wide ...

CVE-2020-25597

An issue was discovered in Xen through 4.14.x. There is mishandling of the constraint that once-valid event channels may not turn invalid. Logic in the handling of event channel operations in Xen assumes that an event channel, once valid, will not become invalid over the life time of a guest...

CVE-2020-25597

An issue was discovered in Xen through 4.14.x. There is mishandling of the constraint that once-valid event channels may not turn invalid. Logic in the handling of event channel operations in Xen assumes that an event channel, once valid, will not become invalid over the life time of a guest...

CVE-2020-25601: Undefined Security Weakness

An issue was discovered in Xen through 4.14.x. There is a lack of preemption in evtchnreset / evtchndestroy. In particular, the FIFO event channel model allows guests to have a large number of event channels active at a time. Closing all of these when resetting all event channels or when cleaning...

CVE-2020-25597: Improper Handling of Exceptional Conditions

An issue was discovered in Xen through 4.14.x. There is mishandling of the constraint that once-valid event channels may not turn invalid. Logic in the handling of event channel operations in Xen assumes that an event channel, once valid, will not become invalid over the life time of a guest...

CVE-2020-25600: Out-of-bounds Write

An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm either bitness ones. 32-bit x86 domain...

CVE-2020-25603

A security flaw was found in Xen. Event channels control structures can be accessed without lock as long as the port is considered to be valid. A malicious guest may be able to cause a hypervisor crash resulting in a denial of service DoS. An information leak and privilege escalation cannot be...

CVE-2020-25601

A security flaw was found in Xen. A lack of preemption in the FIFO event channel model may cause the CPU to spend an almost unbounded amount of processing time. This flaw allows malicious or buggy guest kernels to mount a denial of service DoS attack affecting the entire system. The highest threa...

CVE-2020-25597

A logic flaw was found in the handling of event channel operations in Xen. Operations such as resetting all event channels may involve decreasing one of the bounds checked when determining validity. This flaw allows an unprivileged guest to crash Xen, leading to a denial of service DoS for the...