CVE-2021-3640

A flaw use-after-free in function sco_sock_sendmsg() of the Linux kernel HCI subsystem was found in the way user calls ioct UFFDIO_REGISTER or other way triggers race condition of the call sco_conn_del() together with the call sco_sock_sendmsg() with the expected controllable faulting memory page. A privileged local user could use this flaw to crash the system or escalate their privileges on the system.

• CWE-362
• CWE-416

• https://bugzilla.redhat.com/show_bug.cgi?id=1980646Issue Tracking, Patch, Third Party Advisory
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/bluetooth/sco.c?h=v5.16&id=99c23da0eed4fd20cae8243f2b51e10e66aa0951Patch, Vendor Advisory
• https://github.com/torvalds/linux/commit/99c23da0eed4fd20cae8243f2b51e10e66aa0951Patch, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00011.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00012.htmlMailing List, Third Party Advisory
• https://security.netapp.com/advisory/ntap-20220419-0003/Third Party Advisory
• https://ubuntu.com/security/CVE-2021-3640Patch, Third Party Advisory
• https://www.debian.org/security/2022/dsa-5096Third Party Advisory
• https://www.openwall.com/lists/oss-security/2021/07/22/1Exploit, Mailing List, Third Party Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=1980646Issue Tracking, Patch, Third Party Advisory
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/bluetooth/sco.c?h=v5.16&id=99c23da0eed4fd20cae8243f2b51e10e66aa0951Patch, Vendor Advisory
• https://github.com/torvalds/linux/commit/99c23da0eed4fd20cae8243f2b51e10e66aa0951Patch, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00011.htmlMailing List, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/03/msg00012.htmlMailing List, Third Party Advisory
• https://security.netapp.com/advisory/ntap-20220419-0003/Third Party Advisory
• https://ubuntu.com/security/CVE-2021-3640Patch, Third Party Advisory
• https://www.debian.org/security/2022/dsa-5096Third Party Advisory
• https://www.openwall.com/lists/oss-security/2021/07/22/1Exploit, Mailing List, Third Party Advisory

Published

Mar 3, 2022

Last Modified

Jun 17, 2026

Status

Modified

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