{"id":"PUB-A-174049066","details":"In __configfs_open_file of file.c, there is a possible use-after-free due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.","aliases":["A-174049066","CVE-2021-39656"],"modified":"2026-03-11T06:33:13.803234Z","published":"2021-12-01T00:00:00Z","references":[{"type":"ADVISORY","url":"https://source.android.com/security/bulletin/2021-12-01"},{"type":"FIX","url":"https://android.googlesource.com/kernel/common/+/14fbbc8297728e880070f7b077b3301a8c698ef9"}],"affected":[{"package":{"name":":linux_kernel:","ecosystem":"Android"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":":0"},{"fixed":":2021-12-05"}]}],"versions":["Kernel"],"ecosystem_specific":{"types":["EoP"],"vanir_signatures":[{"deprecated":false,"target":{"file":"fs/configfs/file.c"},"source":"https://android.googlesource.com/kernel/common/+/14fbbc8297728e880070f7b077b3301a8c698ef9","signature_version":"v1","digest":{"line_hashes":["144261116513192799815408308108193273292","280781786439567612260994831180360960883","294553813030166689570977029959468771305","44940190791430184155033322297531087488","285552538128918411554703429691707246082","104919542549789817862532048649785228643","279827945998338001019451597880694582641","6595587290564947242546059497818810327","190916364920762292293447845892620409137","162921567346689495062851703827226368764","301267022441689315400425846168886330072","156405275566311389306309063316725664667","279740195975143045432302307182040504197"],"threshold":0.9},"id":"PUB-A-174049066-039f667e","signature_type":"Line"},{"deprecated":false,"target":{"file":"fs/configfs/file.c","function":"__configfs_open_file"},"source":"https://android.googlesource.com/kernel/common/+/14fbbc8297728e880070f7b077b3301a8c698ef9","signature_version":"v1","digest":{"length":1865,"function_hash":"104396315799143217044677248812266308073"},"id":"PUB-A-174049066-ce7dfc4d","signature_type":"Function"}],"spl":"2021-12-05","fixes":["https://android.googlesource.com/kernel/common/+/14fbbc8297728e880070f7b077b3301a8c698ef9"],"severity":"Moderate"},"database_specific":{"source":"https://storage.googleapis.com/android-osv-test/PUB-A-174049066.json"}}],"schema_version":"1.7.5"}