CVE-2021-23133
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with an admin-level account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 6.7 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Weakness
- CWE-362 · Race condition
- Record status
- Analyzed
Affected
- Linux Kernel < 4.4.269
- Linux Kernel < 4.9.269
- Linux Kernel < 4.14.233
- Linux Kernel < 4.19.191
- Linux Kernel < 5.4.119
- Linux Kernel < 5.10.37
- Linux Kernel < 5.11.21
- Linux Kernel < 5.12.4
Attack profile CVSS 3.1 · 6.7
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2021-23133.md and follow it. Check whether this project is affected by CVE-2021-23133. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
- https://www.openwall.com/lists/oss-security/2021/04/18/2
- http://www.openwall.com/lists/oss-security/2021/05/10/1
- http://www.openwall.com/lists/oss-security/2021/05/10/2
References
- 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CUX2CA63453G34C6KYVBLJXJXEARZI2X/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAEQ3H6HKNO6KUCGRZVYSFSAGEUX23JL/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XZASHZVCOFJ4VU2I3BN5W5EPHWJQ7QWX/
- https://security.netapp.com/advisory/ntap-20210611-0008/
- https://www.openwall.com/lists/oss-security/2021/04/18/2
- 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b
- https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
- https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CUX2CA63453G34C6KYVBLJXJXEARZI2X/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAEQ3H6HKNO6KUCGRZVYSFSAGEUX23JL/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XZASHZVCOFJ4VU2I3BN5W5EPHWJQ7QWX/
- https://security.netapp.com/advisory/ntap-20210611-0008/
- https://www.openwall.com/lists/oss-security/2021/04/18/2