Linux Kernel sctp_destroy_sock race condition
Priority LOW 31CWE-362Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 4 fixed, 1 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
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.
Why it matters now
EPSS 0.00475 41st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Linux Kernel (Linux Kernel): 5.12-rc8Red Hat: 2 advisoriesRed Hat: 4 fixed, 1 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux Kernel | before 5.12-rc8 | 5.12-rc8 | Patch available | CNA |
- Linux Kernel VendorLinux Affected before 5.12-rc8 Fixed in 5.12-rc8 Patch available CNA
CPE configurations NVD · 26
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | before 4.4.269; 4.5 to before 4.9.269; 4.10 to before 4.14.233; 4.15 to before 4.19.191; 4.20 to before 5.4.119; 5.5 to before 5.10.37; 5.11 to before 5.11.21; 5.12 to before 5.12.4 | Vulnerable | Linux |
| cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* | 32 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 34 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
| cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:a:netapp:solidfire_\&_hci_management_node:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:o:broadcom:brocade_fabric_operating_system:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | Broadcom |
| cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 4.4.269; 4.5 to before 4.9.269; 4.10 to before 4.14.233; 4.15 to before 4.19.191; 4.20 to before 5.4.119; 5.5 to before 5.10.37; 5.11 to before 5.11.21; 5.12 to before 5.12.4 Vulnerable ·Linux
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
- cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:a:netapp:solidfire_\&_hci_management_node:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:o:broadcom:brocade_fabric_operating_system:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Broadcom
- cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
Show 16 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
| cpe:2.3:o:netapp:solidfire_baseboard_management_controller_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NetApp |
| cpe:2.3:h:netapp:solidfire_baseboard_management_controller:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NetApp |
- cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h300e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h500e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h700e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
- cpe:2.3:o:netapp:solidfire_baseboard_management_controller_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
- cpe:2.3:h:netapp:solidfire_baseboard_management_controller:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NetApp
Remediation
- Fix · CNA Linux Kernel (Linux Kernel) Fixed in 5.12-rc8
Red Hat 2 advisories
- RHSA-2021:4356 Released 2021-11-09 · Red Hat rating Moderatekernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-348.el8
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-348.el8, kernel-4.18.0-348.el8, kernel-abi-stablelists-4.18.0-348.el8 +19
- RHSA-2021:4140 Released 2021-11-09 · Red Hat rating Moderatekernel-rt security and bug fix update
- Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-348.rt7.130.el8, kernel-rt-core-4.18.0-348.rt7.130.el8, kernel-rt-debug-4.18.0-348.rt7.130.el8 +7
- Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-348.rt7.130.el8, kernel-rt-core-4.18.0-348.rt7.130.el8, kernel-rt-debug-4.18.0-348.rt7.130.el8 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Will not fix |
| Red Hat CodeReady Linux Builder (v. 8) | Fixed | RHSA-2021:4356 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2021:4356 |
| Red Hat Enterprise Linux Real Time (v. 8) | Fixed | RHSA-2021:4140 |
| Red Hat Enterprise Linux Real Time for NFV (v. 8) | Fixed | RHSA-2021:4140 |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-23133
- 2026-10-03 Alias added: GHSA-hp5q-cmxv-w64v
References
Patch 5
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b166a20b07382b8bc1dcee2a448715c9c2c81b5b
- [oss-security] 20210510 Re: CVE-2021-23133: Linux kernel: race condition in sctp sockets
- [oss-security] 20210510 Re: CVE-2021-23133: Linux kernel: race condition in sctp sockets
- [oss-security] 20210510 Re: CVE-2021-23133: Linux kernel: race condition in sctp sockets
- [oss-security] 20210510 Re: CVE-2021-23133: Linux kernel: race condition in sctp sockets
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- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2021-23133 · CVE Program
- CVE-2021-23133 · NVD
- FIRST EPSS
- GHSA-hp5q-cmxv-w64v · GitHub Advisory Database · CC BY 4.0
- CVE-2021-23133 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences