{"id":"UBUNTU-CVE-2026-76642","details":"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.","modified":"2026-09-16T14:01:59.214702967Z","published":"2026-09-03T13:06:00Z","upstream":["CVE-2026-76642"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-76642"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-76642"},{"type":"REPORT","url":"https://github.com/util-linux/util-linux/security/advisories/GHSA-m25x-3hj9-m26f"}],"affected":[{"package":{"name":"util-linux","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/util-linux?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.20.1-5.1ubuntu9","2.20.1-5.1ubuntu10","2.20.1-5.1ubuntu11","2.20.1-5.1ubuntu12","2.20.1-5.1ubuntu13","2.20.1-5.1ubuntu14","2.20.1-5.1ubuntu15","2.20.1-5.1ubuntu16","2.20.1-5.1ubuntu17","2.20.1-5.1ubuntu18","2.20.1-5.1ubuntu19","2.20.1-5.1ubuntu20","2.20.1-5.1ubuntu20.1","2.20.1-5.1ubuntu20.2","2.20.1-5.1ubuntu20.3","2.20.1-5.1ubuntu20.4","2.20.1-5.1ubuntu20.6","2.20.1-5.1ubuntu20.7","2.20.1-5.1ubuntu20.9"],"ecosystem_specific":{"binaries":[{"binary_version":"1:2.20.1-5.1ubuntu20.9","binary_name":"bsdutils"},{"binary_name":"libblkid1","binary_version":"2.20.1-5.1ubuntu20.9"},{"binary_version":"2.20.1-5.1ubuntu20.9","binary_name":"libmount1"},{"binary_version":"2.20.1-5.1ubuntu20.9","binary_name":"libuuid1"},{"binary_name":"mount","binary_version":"2.20.1-5.1ubuntu20.9"},{"binary_version":"2.20.1-5.1ubuntu20.9","binary_name":"util-linux"},{"binary_version":"2.20.1-5.1ubuntu20.9","binary_name":"util-linux-locales"},{"binary_name":"uuid-runtime","binary_version":"2.20.1-5.1ubuntu20.9"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-76642.json"}},{"package":{"name":"util-linux","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/util-linux?arch=source&distro=esm-infra%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.26.2-6ubuntu3","2.27-3ubuntu1","2.27.1-1ubuntu2","2.27.1-1ubuntu3","2.27.1-1ubuntu4","2.27.1-3ubuntu1","2.27.1-4ubuntu1","2.27.1-6ubuntu1","2.27.1-6ubuntu2","2.27.1-6ubuntu3","2.27.1-6ubuntu3.1","2.27.1-6ubuntu3.2","2.27.1-6ubuntu3.3","2.27.1-6ubuntu3.4","2.27.1-6ubuntu3.6","2.27.1-6ubuntu3.7","2.27.1-6ubuntu3.8","2.27.1-6ubuntu3.9","2.27.1-6ubuntu3.10","2.27.1-6ubuntu3.10+esm2"],"ecosystem_specific":{"binaries":[{"binary_version":"1:2.27.1-6ubuntu3.10+esm2","binary_name":"bsdutils"},{"binary_name":"libblkid1","binary_version":"2.27.1-6ubuntu3.10+esm2"},{"binary_version":"2.27.1-6ubuntu3.10+esm2","binary_name":"libfdisk1"},{"binary_name":"libmount1","binary_version":"2.27.1-6ubuntu3.10+esm2"},{"binary_version":"2.27.1-6ubuntu3.10+esm2","binary_name":"libsmartcols1"},{"binary_version":"2.27.1-6ubuntu3.10+esm2","binary_name":"libuuid1"},{"binary_version":"2.27.1-6ubuntu3.10+esm2","binary_name":"mount"},{"binary_name":"util-linux","binary_version":"2.27.1-6ubuntu3.10+esm2"},{"binary_name":"util-linux-locales","binary_version":"2.27.1-6ubuntu3.10+esm2"},{"binary_version":"2.27.1-6ubuntu3.10+esm2","binary_name":"uuid-runtime"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-76642.json"}},{"package":{"name":"util-linux","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/util-linux?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.30.1-0ubuntu4","2.30.2-0.1ubuntu1","2.30.2-0.1ubuntu2","2.30.2-0.1ubuntu3","2.31.1-0.4ubuntu2","2.31.1-0.4ubuntu3","2.31.1-0.4ubuntu3.1","2.31.1-0.4ubuntu3.2","2.31.1-0.4ubuntu3.3","2.31.1-0.4ubuntu3.4","2.31.1-0.4ubuntu3.5","2.31.1-0.4ubuntu3.6","2.31.1-0.4ubuntu3.7"],"ecosystem_specific":{"binaries":[{"binary_name":"bsdutils","binary_version":"1:2.31.1-0.4ubuntu3.7"},{"binary_name":"fdisk","binary_version":"2.31.1-0.4ubuntu3.7"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"libblkid1"},{"binary_name":"libfdisk1","binary_version":"2.31.1-0.4ubuntu3.7"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"libmount1"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"libsmartcols1"},{"binary_name":"libuuid1","binary_version":"2.31.1-0.4ubuntu3.7"},{"binary_name":"mount","binary_version":"2.31.1-0.4ubuntu3.7"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"rfkill"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"setpriv"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"util-linux"},{"binary_version":"2.31.1-0.4ubuntu3.7","binary_name":"util-linux-locales"},{"binary_name":"uuid-runtime","binary_version":"2.31.1-0.4ubuntu3.7"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-76642.json"}},{"package":{"name":"util-linux","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/util-linux?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.34-0.1ubuntu2","2.34-0.1ubunt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