CVE-2026-71224

A stack overflow vulnerability was found in gfs2-utils. The metadata walk code in metawalk.c uses alloca() with an untrusted inode height value from on-disk metadata without bounds validation, causing stack exhaustion and a denial of service when processing crafted GFS2 filesystem images.

This vulnerability is assessed as Moderate impact because the alloca-based stack exhaustion results in a process crash (SIGSEGV) rather than controlled memory corruption. RHEL stack guard pages prevent the overflow from reaching other memory regions, confining the impact to denial of service. Exploitation requires local access and user interaction (an administrator must run fsck.gfs2 or other gfs2-utils tools on a crafted GFS2 filesystem image). The vulnerability does not affect the kernel GFS2 driver, which validates i_height against sd_max_height.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Run gfs2-utils tools in a containerized or VM-isolated environment when processing potentially compromised or untrusted GFS2 filesystem images. Disable automatic fsck at boot for GFS2 filesystems until patches are applied by setting fs_passno to 0 in /etc/fstab. Use ulimit -s to reduce the stack size limit, converting potential exploitation into a controlled crash.