CVE-2023-4273

Published: 9 August 2023

A flaw was found in the exFAT driver of the Linux kernel. The vulnerability exists in the implementation of the file name reconstruction function, which is responsible for reading file name entries from a directory index and merging file name parts belonging to one file into a single long file name. Since the file name characters are copied into a stack variable, a local privileged attacker could use this flaw to overflow the kernel stack.

From the Ubuntu Security Team

Maxim Suhanov discovered that the exFAT file system implementation in the Linux kernel did not properly check a file name length, leading to an out- of-bounds write vulnerability. An attacker could use this to construct a malicious exFAT image that, when mounted and operated on, could cause a denial of service (system crash) or possibly execute arbitrary code.

Status

Severity score breakdown

References

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-4273
• https://dfir.ru/2023/08/23/cve-2023-4273-a-vulnerability-in-the-linux-exfat-driver/
• https://access.redhat.com/security/cve/CVE-2023-4273
• https://ubuntu.com/security/notices/USN-6343-1
• https://ubuntu.com/security/notices/USN-6385-1
• NVD
• Launchpad
• Debian

Bugs

• https://bugzilla.redhat.com/show_bug.cgi?id=2221609
• https://bugzilla.suse.com/show_bug.cgi?id=1214120