evtchn: Race between FIFO expand and reset
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.3epss 0.2%
exploitation probability
0.2%top 88% of all CVEs
observed exploitation
nono source reports it
The EVTCHNOP_expand_array hypercall checks for whether FIFO event
channels are enabled, but without holding the correct lock. It can race
with EVTCHNOP_reset, resulting in dereferencing a NULL pointer.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Affected products
Xen · Xen