CVE-2026-71219 PUBLISHED

Gfs2-utils: gfs2-utils: stack overflow via alloca(1<<di_depth) in hash table traversal

Assigner: redhat
Reserved: 05.08.2026 Published: 03.09.2026 Updated: 03.09.2026

A stack overflow vulnerability was found in gfs2-utils. The hash table traversal code in metawalk.c uses alloca() with an exponentially-derived size from the untrusted on-disk di_depth field without bounds validation. A crafted GFS2 filesystem image with a large di_depth value causes stack exhaustion and a denial of service when processed by fsck.gfs2, gfs2_edit, or savemeta.

Metrics

CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS Score: 4.7

Product Status

Vendor Red Hat
Product Red Hat Enterprise Linux 7
Versions Default: affected
Vendor Red Hat
Product Red Hat Enterprise Linux 8
Versions Default: affected
Vendor Red Hat
Product Red Hat Enterprise Linux 9
Versions Default: affected

Workarounds

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.

Credits

  • Red Hat would like to thank Tristan Madani (Talence Security) for reporting this issue.

References

Problem Types

  • Allocation of Resources Without Limits or Throttling CWE