CVE-2026-76642

CVE-2026-76642

util-linux versions through 2.41.5 and 2.42.2 fail to check mount helper exit status before running post-mount hooks, allowing unprivileged users to execute privileged operations on pre-existing filesystems. Attackers can exploit X-mount.idmap or X-mount.owner hooks to clone filesystems with inherited suid bits or modify target inode permissions after a helper fails, achieving privilege escalation.

EPSS: 0.002 (6.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-76642?
CVE-2026-76642 is a high-severity vulnerability, classified under CWE-390. CVSS score: 7.8/10. Published 2026-09-03.
How severe is CVE-2026-76642?
High severity. CVSS v3 base score is 7.8 out of 10.