CVE-2023-1192: Use-after-free in smb2_is_status_io_timeout()

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-11-01 · updated 2026-06-17
Weakness: CWE-416

Description

A use-after-free flaw was found in smb2_is_status_io_timeout() in CIFS in the Linux Kernel. After CIFS transfers response data to a system call, there are still local variable points to the memory region, and if the system call frees it faster than CIFS uses it, CIFS will access a free memory region, leading to a denial of service.

Affected products

Linux kernel: before 6.4 — fixed in 6.4
Red Hat Enterprise Linux: 8.0, 9.0

How to fix

Upgrade to a fixed version: Linux kernel 6.4. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2023-1192
https://bugzilla.redhat.com/show_bug.cgi?id=2154178
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d527f51331cace562393a8038d870b3e9916686f
https://access.redhat.com/security/cve/CVE-2023-1192
https://bugzilla.redhat.com/show_bug.cgi?id=2154178
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d527f51331cace562393a8038d870b3e9916686f

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