Linux kernel (CIFS): Use-after-free vulnerability allows data integrity compromise and denial of service
CVE: CVE-2023-53751
Component: kernel
CWE: CWE-825
Severity: Moderate
CVSS v3: 7.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H
Release date: 2023-01-01T00:00:00+00:00

A flaw was found in the Linux kernel's Common Internet File System (CIFS) component. This use-after-free vulnerability occurs due to improper handling of server hostname information during connection re-establishment. An attacker on an adjacent network could exploit this, potentially leading to a compromise of data integrity or a denial of service.

Statement: This MODERATE impact use-after-free flaw in the Linux kernel's CIFS component. An attacker on an adjacent network could exploit this vulnerability during connection re-establishment, potentially leading to data integrity compromise or a denial of service.

Remediation:
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
To mitigate this issue, prevent the `cifs` kernel module from loading if CIFS functionality is not required. Create a file named `/etc/modprobe.d/disable-cifs.conf` with the following content:

```
install cifs /bin/true
```

This will prevent the `cifs` module from being loaded automatically. A system reboot is required for this change to take effect. Note that disabling the `cifs` module will prevent the system from mounting CIFS shares.