| Name | CVE-2015-4177 |
| Description | The collect_mounts function in fs/namespace.c in the Linux kernel before 4.0.5 does not properly consider that it may execute after a path has been unmounted, which allows local users to cause a denial of service (system crash) by leveraging user-namespace root access for an MNT_DETACH umount2 system call. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | fixed |
| stretch (security) | 4.9.320-2 | fixed |
| stretch (lts), stretch | 4.9.320-3 | fixed |
| buster (security), buster, buster (lts) | 4.19.316-1 | fixed |
| bullseye | 5.10.223-1 | fixed |
| bullseye (security) | 5.10.226-1 | fixed |
| bookworm | 6.1.115-1 | fixed |
| bookworm (security) | 6.1.119-1 | fixed |
| trixie | 6.12.5-1 | fixed |
| sid | 6.12.6-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| linux | source | (unstable) | (not affected) | | | |
| linux-2.6 | source | (unstable) | (not affected) | | | |
Notes
- linux <not-affected> (Commit was applied to 4.0.2 as well but fixed in Debian by two subsequent commits)
Debian both applies "mnt: Fail collect_mounts when applied to unmounted mounts"
and "fs_pin: Allow for the possibility that m_list or s_list go unused." in
4.0.2-1
- linux-2.6 <not-affected> (Introduced and fixed in 4.1-rc1 upstream)
Introduced by: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce07d891a0891d3c0d0c2d73d577490486b809e1 (v4.1-rc1)
Fixed by: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=cd4a40174b71acd021877341684d8bb1dc8ea4ae (v4.1-rc1)
https://www.openwall.com/lists/oss-security/2015/05/29/5