CVE-2021-3573
kernel: use-after-free in function hci_sock_bound_ioctl()
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · June 8, 2021
Updated · June 28, 2026
Description
A flaw use-after-free in function hci_sock_bound_ioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hci_unregister_dev() together with one of the calls hci_sock_blacklist_add(), hci_sock_blacklist_del(), hci_get_conn_info(), hci_get_auth_info(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system.
Statement
This issue is rated as having a Moderate impact because of the privileges (CAP_NET_ADMIN in initial namespace) required for exploiting the issue.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising easThe required privileges is CAP_NET_ADMIN capabilities. This would require a privileged user with CAP_SYS_ADMIN or root to be able to abuse this flaw reducing its attack space.e of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 6.7CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE-788 · Access of Memory Location After End of Buffer