| Name | CVE-2017-18078 |
| Description | systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on hardlinked files even if the fs.protected_hardlinks sysctl is turned off, which allows local users to bypass intended access restrictions via vectors involving a hard link to a file for which the user lacks write access, as demonstrated by changing the ownership of the /etc/passwd file. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-1762-1, ELA-115-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| systemd (PTS) | jessie, jessie (lts) | 215-17+deb8u15 | fixed |
| stretch (security) | 232-25+deb9u14 | vulnerable | |
| stretch (lts), stretch | 232-25+deb9u17 | vulnerable | |
| buster, buster (lts) | 241-7~deb10u11 | fixed | |
| buster (security) | 241-7~deb10u10 | fixed | |
| bullseye | 247.3-7+deb11u5 | fixed | |
| bullseye (security) | 247.3-7+deb11u6 | fixed | |
| bookworm | 252.30-1~deb12u2 | fixed | |
| sid, trixie | 256.7-3 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| systemd | source | wheezy | 44-11+deb7u7 | ELA-115-1 | ||
| systemd | source | jessie | 215-17+deb8u12 | DLA-1762-1 | ||
| systemd | source | (unstable) | 237-1 | unimportant |
https://github.com/systemd/systemd/issues/7736
https://github.com/systemd/systemd/commit/5579f85663d10269e7ac7464be6548c99cea4ada (v237)
Neutralised by kernel hardening