CVE-2023-54063: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-54063 is an out-of-bounds (OOB) read vulnerability in the Linux kernel's NTFS3 filesystem driver, specifically in the indx_insert_into_buffer() function in fs/ntfs3/index.c. The flaw was discovered via Syzbot fuzzing and disclosed on December 24, 2025. It affects Linux kernel versions starting from 5.15 (when ntfs3 was introduced) up to the patched stable releases: 5.15.111, 6.1.28, 6.2.15, 6.3.2, and 6.4. No CVSS score has been officially assigned; the EPSS score is approximately 0.00018, indicating very low exploitation probability (Feedly, ENISA EUVD).

The root cause is an improper validation of index buffer header fields in the NTFS3 driver (CWE-125: Out-of-bounds Read). Specifically, when the INDEX_BUFFER *index member of struct indx_node contains a corrupted or maliciously crafted value where the __le32 used field in struct INDEX_HDR exceeds the __le32 total field, a subsequent call to memmove() in indx_insert_into_buffer() at fs/ntfs3/index.c:1755 reads beyond the allocated slab buffer. The fix adds a bounds check in hdr_find_e() to validate these fields before the memmove is invoked. Exploitation requires mounting a specially crafted NTFS3 filesystem image, making it a local attack vector (Feedly, ENISA EUVD).

Successful exploitation of this vulnerability can cause a kernel slab-out-of-bounds read, which may lead to information disclosure of kernel memory contents or a kernel panic resulting in a denial of service. The vulnerability is confined to systems where an attacker can mount or interact with a crafted NTFS3 filesystem image, limiting the scope primarily to local privilege escalation scenarios or denial of service. There is no evidence of remote exploitability or lateral movement potential (Feedly, ENISA EUVD).

The Linux kernel stable team has released patches addressing this vulnerability across multiple stable branches. Fixed versions include Linux 5.15.111, 6.1.28, 6.2.15, 6.3.2, and 6.4. Administrators should update to the appropriate patched kernel version for their distribution. As a workaround, systems that do not require NTFS3 filesystem support can blacklist or disable the ntfs3 kernel module (echo 'blacklist ntfs3' >> /etc/modprobe.d/blacklist.conf) to eliminate the attack surface (ENISA EUVD, Kernel Patches).