CVE-2020-29566
Description
An issue was discovered in Xen through 4.14.x. When they require assistance from the device model, x86 HVM guests must be temporarily de-scheduled. The device model will signal Xen when it has completed its operation, via an event channel, so that the relevant vCPU is rescheduled. If the device model were to signal Xen without having actually completed the operation, the de-schedule / re-schedule cycle would repeat. If, in addition, Xen is resignalled very quickly, the re-schedule may occur before the de-schedule was fully complete, triggering a shortcut. This potentially repeating process uses ordinary recursive function calls, and thus could result in a stack overflow. A malicious or buggy stubdomain serving a HVM guest can cause Xen to crash, resulting in a Denial of Service (DoS) to the entire host. Only x86 systems are affected. Arm systems are not affected. Only x86 stubdomains serving HVM guests can exploit the vulnerability.
EPSS (Exploit Prediction Scoring System)
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.
EPSS Score Trend (Last 90 Days)
Uncontrolled Recursion
DraftCommon Consequences
Applicable Platforms
Debian Linux by Debian
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
Fedora by Fedoraproject
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
Xen by Xen
cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:*
Fedora by Fedoraproject
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*