High severity · published Apr 22, 2021
CVE-2021-23133
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…
7.0
CVSS
0.5%
EPSS
No
On KEV
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
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
before 4.4.269; 4.5 before 4.9.269; 4.10 before 4.14.233; 4.15 before 4.19.191; 4.20 before 5.4.119; 5.5 before 5.10.37; +2 more · source: NVD
BF
Brocade Fabric Operating System · Broadcom
All versions, or not specified · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
FE
Fedora · Fedoraproject
32; 33; 34 · source: NVD
HF
H300e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H300s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410c Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H700e Firmware · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-23133
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-23133
Mailing List
http://www.openwall.com/lists/oss-security/2021/05/10/1
Mailing List
http://www.openwall.com/lists/oss-security/2021/05/10/2
Mailing List
http://www.openwall.com/lists/oss-security/2021/05/10/3
Mailing List
http://www.openwall.com/lists/oss-security/2021/05/10/4
Mailing List
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b
Mitigation
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
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