umtx Kernel panic or Use-After-Free
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.8epss 0.7%
exploitation probability
0.7%top 51% of all CVEs
observed exploitation
nono source reports it
Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of UMTX_OP_SHM can lead to decreasing the reference count of the object representing the mapping too many times, causing it to be freed too early.
A malicious code exercizing the UMTX_SHM_DESTROY sub-request in parallel can panic the kernel or enable further Use-After-Free attacks, potentially including code execution or Capsicum sandbox escape.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
FreeBSD · FreeBSD