Description
When mount.ecrpytfs_private before version 87-0ubuntu1.2 calls setreuid() it doesn't also set the effective group id. So when it creates the new version, mtab.tmp, it's created with the group id of the user running mount.ecryptfs_private.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ecryptfs-utils | 92-1 | — |
| Debian 13 | ecryptfs-utils | 92-1 | — |
| Debian 12 | ecryptfs-utils | 92-1 | — |
| Debian 6.0 | ecryptfs-utils | 83-4+squeeze1 | DSA-2382-1 |
| Debian 5.0 | ecryptfs-utils | 68-1+lenny1 | DSA-2382-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | ecryptfs-utils +2 | 82-6.el6_1.3 | RHSA-2011:1241 |
| RHEL 5 | ecryptfs-utils +2 | 75-5.el5_7.2 | RHSA-2011:1241 |
Advisories 2
- RHSA-2011:1241 Red Hat Security Advisory: ecryptfs-utils security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-2382-1 ecryptfs-utils - multiple Debian Security (DSA / DLA) · Mar 9, 2026