high
8.8
CWE
362 416
EPSS
0.045%
Advisory Published
CVE Published
Updated
Advisory Published

CVE-2023-6546: Linux Kernel GSM Multiplexing Race Condition Local Privilege Escalation Vulnerability

First published: Thu Dec 21 2023(Updated: )

A race condition was found in the GSM 0710 tty multiplexor (drivers/tty/n_gsm.c) in the Linux kernel. The flaw occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled and leads to a use-after-free on a struct gsm_dlci while restarting the gsm mux. A local unprivileged user could use this vulnerability to escalate their privileges on the system. ZDI Security Advisory: <a href="https://www.zerodayinitiative.com/advisories/ZDI-CAN-20527">https://www.zerodayinitiative.com/advisories/ZDI-CAN-20527</a> Upstream fix: <a href="https://github.com/torvalds/linux/commit/3c4f8333b582487a2d1e02171f1465531cde53e3">https://github.com/torvalds/linux/commit/3c4f8333b582487a2d1e02171f1465531cde53e3</a>

Credit: secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
redhat/kernel<6.5
6.5
Linux kernel
Linux Kernel<6.5
Linux Kernel=6.5-rc1
Linux Kernel=6.5-rc2
Linux Kernel=6.5-rc3
Linux Kernel=6.5-rc4
Linux Kernel=6.5-rc5
Linux Kernel=6.5-rc6
Fedora=39
Red Hat Enterprise Linux=8.0
Red Hat Enterprise Linux=9.0
IBM QRadar Security Information and Event Manager<=7.5 - 7.5.0 UP8 IF01

Remedy

https://bugzilla.redhat.com/show_bug.cgi?id=2255498

Remedy

https://github.com/torvalds/linux/commit/3c4f8333b582487a2d1e02171f1465531cde53e3

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Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2023-6546?

    CVE-2023-6546 has been categorized as a high-severity vulnerability due to its potential to cause a use-after-free condition.

  • How do I fix CVE-2023-6546?

    To remediate CVE-2023-6546, ensure that you upgrade to a patched version of the Linux kernel or the affected software that addresses this flaw.

  • Which systems are affected by CVE-2023-6546?

    CVE-2023-6546 affects several Linux kernel versions up to 6.5, as well as specific versions of IBM QRadar SIEM and Red Hat Enterprise Linux.

  • What type of vulnerability is CVE-2023-6546?

    CVE-2023-6546 is classified as a race condition vulnerability that leads to a use-after-free error in the Linux kernel.

  • Can CVE-2023-6546 be exploited remotely?

    Exploitation of CVE-2023-6546 typically requires local access to the system, as it involves interactions between threads on a tty file descriptor.

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