Vulnerability in Linux Kernel
CVE-2021-3573
A 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. This flaw affects the Linux kernel versions prior to 5.13-rc5.
Vulnerability class: Race Condition
EPSS: 0.004 (29.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux Linux_kernel — versions 5.13
- Fedoraproject Fedora — versions 34
- Redhat Enterprise_linux — versions 6.0, 7.0, 8.0
- N/a Kernel — versions kernel 5.13-rc5
Weakness classification (CWE)
Public proof-of-concept exploits
- ARPSyndicate/cvemon
- hardenedvault/ved
- kdn111/linux-kernel-exploitation
- khanhdn111/linux-kernel-exploitation
- khanhdz-06/linux-kernel-exploitation
- khanhdz191/linux-kernel-exploitation
- khanhhdz/linux-kernel-exploitation
- khanhhdz06/linux-kernel-exploitation
- khanhnd123/linux-kernel-exploitation
- khnhdz/linux-kernel-exploitation
References
- secalert@redhat.com (Third Party Advisory, Issue Tracking)
- secalert@redhat.com (Patch, Vendor Advisory)
- secalert@redhat.com (Exploit, Mailing List, Third Party Advisory)
- secalert@redhat.com (mailing-list)
Frequently asked questions
- What is CVE-2021-3573?
- CVE-2021-3573 is a medium-severity vulnerability in Linux Kernel, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 6.4/10. Published 2021-08-13.
- How severe is CVE-2021-3573?
- Medium severity. CVSS v3 base score is 6.4 out of 10.
- Is CVE-2021-3573 known to be exploited?
- 16 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.