CVE-2023-6546

Kernel: gsm multiplexing race condition leads to privilege escalation

Description

A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.

Remediation

Workaround:

  • This flaw can be mitigated by preventing the affected `n_gsm` kernel module from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.

Categories

7.0
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.24%
Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com
Affected: Red Hat Red Hat Enterprise Linux 8
Affected: Red Hat Red Hat Enterprise Linux 8
Affected: Red Hat Red Hat Enterprise Linux 8
Affected: Red Hat Red Hat Enterprise Linux 8.2 Advanced Update Support
Affected: Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
Affected: Red Hat Red Hat Enterprise Linux 8.4 Telecommunications Update Service
Affected: Red Hat Red Hat Enterprise Linux 8.4 Telecommunications Update Service
Affected: Red Hat Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions
Affected: Red Hat Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions
Affected: Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9
Affected: Red Hat Red Hat Enterprise Linux 9
Affected: Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support
Affected: Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support
Affected: Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat RHOL-5.7-RHEL-8
Affected: Red Hat Red Hat Enterprise Linux 6
Affected: Red Hat Red Hat Enterprise Linux 7
Affected: Red Hat Red Hat Enterprise Linux 7
Affected: Red Hat Red Hat Enterprise Linux 9
Published at:
Updated at:

References

Link Tags
https://access.redhat.com/errata/RHSA-2024:0930 vendor advisory
https://access.redhat.com/errata/RHSA-2024:0937 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1018 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1019 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1055 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1250 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1253 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1306 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1607 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1612 vendor advisory
https://access.redhat.com/errata/RHSA-2024:1614 vendor advisory
https://access.redhat.com/errata/RHSA-2024:2093 vendor advisory
https://access.redhat.com/errata/RHSA-2024:2394 vendor advisory
https://access.redhat.com/errata/RHSA-2024:2621 vendor advisory
https://access.redhat.com/errata/RHSA-2024:2697 vendor advisory
https://access.redhat.com/errata/RHSA-2024:4577 vendor advisory
https://access.redhat.com/errata/RHSA-2024:4729 vendor advisory
https://access.redhat.com/errata/RHSA-2024:4731 vendor advisory
https://access.redhat.com/errata/RHSA-2024:4970 vendor advisory
https://access.redhat.com/security/cve/CVE-2023-6546 third party advisory vdb entry
https://bugzilla.redhat.com/show_bug.cgi?id=2255498 patch third party advisory issue tracking
https://github.com/torvalds/linux/commit/3c4f8333b582487a2d1e02171f1465531cde53e3 patch
https://www.zerodayinitiative.com/advisories/ZDI-CAN-20527
http://www.openwall.com/lists/oss-security/2024/04/10/18
http://www.openwall.com/lists/oss-security/2024/04/10/21
http://www.openwall.com/lists/oss-security/2024/04/11/7
http://www.openwall.com/lists/oss-security/2024/04/11/9
http://www.openwall.com/lists/oss-security/2024/04/12/1
http://www.openwall.com/lists/oss-security/2024/04/12/2
http://www.openwall.com/lists/oss-security/2024/04/16/2
http://www.openwall.com/lists/oss-security/2024/04/17/1

Frequently Asked Questions

What is the severity of CVE-2023-6546?
CVE-2023-6546 has been scored as a high severity vulnerability.
How to fix CVE-2023-6546?
As a workaround for remediating CVE-2023-6546: This flaw can be mitigated by preventing the affected `n_gsm` kernel module from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.
Is CVE-2023-6546 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6546 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-6546?
CVE-2023-6546 affects Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 8.2 Advanced Update Support, Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Red Hat Enterprise Linux 8.4 Telecommunications Update Service, Red Hat Red Hat Enterprise Linux 8.4 Telecommunications Update Service, Red Hat Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions, Red Hat Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions, Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support, Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support, Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support, Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support, Red Hat Red Hat Enterprise Linux 9, Red Hat Red Hat Enterprise Linux 9, Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support, Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support, Red Hat Red Hat Enterprise Linux 9.0 Extended Update Support, Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support, Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support, Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support, Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat RHOL-5.7-RHEL-8, Red Hat Red Hat Enterprise Linux 6, Red Hat Red Hat Enterprise Linux 7, Red Hat Red Hat Enterprise Linux 7, Red Hat Red Hat Enterprise Linux 9.
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