Copyright © 2012 Red Hat, Inc. All rights reserved. Important 2026-06-24T00:00:00 kernel: Linux kernel OMFS: Arbitrary code execution via crafted filesystem image 7.0 CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H CWE-787

In the Linux kernel, the following vulnerability has been resolved: fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START omfs_fill_super() rejects oversized s_sys_blocksize values (> PAGE_SIZE), but it does not reject values smaller than OMFS_DIR_START (0x1b8 = 440). Later, omfs_make_empty() uses sbi->s_sys_blocksize - OMFS_DIR_START as the length argument to memset(). Since s_sys_blocksize is u32, a crafted filesystem image with s_sys_blocksize < OMFS_DIR_START causes an unsigned underflow there, wrapping to a value near 2^32. That drives a ~4 GiB memset() from bh->b_data + OMFS_DIR_START and overwrites kernel memory far beyond the backing block buffer. Add the corresponding lower-bound check alongside the existing upper-bound check in omfs_fill_super(), so that malformed images are rejected during superblock validation before any filesystem data is processed.

A flaw was found in the Linux kernel's OMFS filesystem. A local attacker could exploit this by providing a specially crafted filesystem image. When processing the image, an integer underflow occurs, leading to an out-of-bounds write that overwrites kernel memory. This could result in a system crash or potentially allow for arbitrary code execution.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53130 https://nvd.nist.gov/vuln/detail/CVE-2026-53130 https://lore.kernel.org/linux-cve-announce/2026062418-CVE-2026-53130-c204@gregkh/T