CVE-2021-23133 Information

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.

CVSS Vector

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

Reference

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b https://www.openwall.com/lists/oss-security/2021/04/18/2 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PAEQ3H6HKNO6KUCGRZVYSFSAGEUX23JL/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CUX2CA63453G34C6KYVBLJXJXEARZI2X/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XZASHZVCOFJ4VU2I3BN5W5EPHWJQ7QWX/ http://www.openwall.com/lists/oss-security/2021/05/10/1 http://www.openwall.com/lists/oss-security/2021/05/10/2 http://www.openwall.com/lists/oss-security/2021/05/10/3 http://www.openwall.com/lists/oss-security/2021/05/10/4 https://security.netapp.com/advisory/ntap-20210611-0008/ https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.0