Description
The seunshare_mount function in sandbox/seunshare.c in seunshare in certain Red Hat packages of policycoreutils 2.0.83 and earlier in Red Hat Enterprise Linux (RHEL) 6 and earlier, and Fedora 14 and earlier, mounts a new directory on top of /tmp without assigning root ownership and the sticky bit to this new directory, which allows local users to replace or delete arbitrary /tmp files, and consequently cause a denial of service or possibly gain privileges, by running a setuid application that relies on /tmp, as demonstrated by the ksu application.
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.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | policycoreutils +4 | 2.0.83-19.8.el6_0 | RHSA-2011:0414 |
| RHEL 6 | selinux-policy +4 | 3.7.19-54.el6_0.5 | RHSA-2011:0414 |
Advisories 1
- RHSA-2011:0414 Red Hat Security Advisory: policycoreutils security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=633544
- 44034 third-party-advisory
- 20110222 Developers should not rely on the stickiness of /tmp on Red Hat Linux mailing-list
- 1025291 vdb-entry
- http://pkgs.fedoraproject.org/gitweb/?p=policycoreutils.git%3Ba=blob%3Bf=policycoreutils-rhat.patch%3Bh=d4db5bc06027de23d12a4b3f18fa6f9b1517df27%3Bhb=HEAD#l2197
- policycoreutils-seunshare-symlink(65641) vdb-entry
- 43844 third-party-advisory
- ADV-2011-0701 vdb-entry
- FEDORA-2011-3043 vendor-advisory
- RHSA-2011:0414 vendor-advisory
- ADV-2011-0864 vdb-entry
- 46510 vdb-entry
- [oss-security] 20110222 CVE Request mailing-list
- 43415 third-party-advisory
- [oss-security] 20110223 Re: CVE Request mailing-list