Description

A race condition in Linux kernel SCTP sockets (net/sctp/socket.c) before 5.12-rc8 can lead to kernel privilege escalation from the context of a network service or an unprivileged process. If sctp_destroy_sock is called without sock_net(sk)->sctp.addr_wq_lock then an element is removed from the auto_asconf_splist list without any proper locking. This can be exploited by an attacker with network service privileges to escalate to root or from the context of an unprivileged user directly if a BPF_CGROUP_INET_SOCK_CREATE is attached which denies creation of some SCTP socket.

Metrics

CVSS 3.1 7.0/10CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-362

Affected software

Vendor	Product	Versions
Linux Kernel	Linux Kernel	>= unspecified, < 5.12-rc8

References

http://www.openwall.com/lists/oss-security/2021/05/10/1Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/2Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/3Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/4Mailing List, Patch, Third Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5bMailing List, Patch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.htmlMitigation, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.htmlMitigation, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CUX2CA63453G34C6KYVBLJXJXEARZI2X/Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAEQ3H6HKNO6KUCGRZVYSFSAGEUX23JL/Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XZASHZVCOFJ4VU2I3BN5W5EPHWJQ7QWX/Third Party Advisory
https://security.netapp.com/advisory/ntap-20210611-0008/Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/04/18/2Exploit, Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/1Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/2Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/3Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/05/10/4Mailing List, Patch, Third Party Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5bMailing List, Patch, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.htmlMitigation, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.htmlMitigation, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CUX2CA63453G34C6KYVBLJXJXEARZI2X/Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAEQ3H6HKNO6KUCGRZVYSFSAGEUX23JL/Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XZASHZVCOFJ4VU2I3BN5W5EPHWJQ7QWX/Third Party Advisory
https://security.netapp.com/advisory/ntap-20210611-0008/Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/04/18/2Exploit, Mailing List, Patch, Third Party Advisory

Timeline

Published: Apr 22, 2021
Last modified: Jul 30, 2026
NVD status: Analyzed

CVE-2021-23133