A crafted message in the BuildKit low-level build API can be used to remove the contents of the /tmp directory. The action that can normally be used to delete files inside the build container rootfs can escape into the real host temp directory.
Exploitability
AV:LAC:LAT:PPR:NUI:AVulnerable System
VC:NVI:LVA:LSubsequent System
SC:NSI:NSA:N3.3/CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:NInput Validation