Description
A vulnerability was recently discovered in the rpc.mountd daemon in the nfs-utils package for Linux, that allows a NFSv3 client to escalate the privileges assigned to it in the /etc/exports file at mount time. In particular, it allows the client to access any subdirectory or subtree of an exported directory, regardless of the set file permissions, and regardless of any 'root_squash' or 'all_squash' attributes that would normally be expected to apply to that client.
Affected products
redhat: openshift container platform; redhat: enterprise linux; linux-nfs: nfs-utils
References10
- access.redhat.com/errata/RHSA-2026:3938 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:3939 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:3940 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:3941 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:3942 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:5127
- access.redhat.com/errata/RHSA-2026:5606
- access.redhat.com/errata/RHSA-2026:5867
- access.redhat.com/errata/RHSA-2026:5873
- access.redhat.com/errata/RHSA-2026:5877
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 44 · as of 12 November 2026
- CWE
- CWE-279CWE-732
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