{"id":"CVE-2017-18078","aliases":["DEBIAN-CVE-2017-18078","DLA-1762-1","EUVD-2017-9215","GHSA-g2wx-phqf-j84q","SUSE-SU-2018:0546-1","UBUNTU-CVE-2017-18078","openSUSE-SU-2024:11420-1"],"status":"published","title":"systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on...","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 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List","Third Party Advisory","advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2018/01/29/3","tags":["mailing-list","x_refsource_MLIST","x_transferred","Exploit","Mailing List","Third Party Advisory","evidence"]},{"url":"https://www.exploit-db.com/exploits/43935/","tags":["exploit","x_refsource_EXPLOIT-DB","x_transferred","Exploit","Third Party Advisory","VDB Entry","evidence"]},{"url":"https://github.com/systemd/systemd/issues/7736","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Third Party Advisory","report"]},{"url":"http://packetstormsecurity.com/files/146184/systemd-Local-Privilege-Escalation.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","VDB Entry","evidence"]},{"url":"https://www.openwall.com/lists/oss-security/2018/01/29/4","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://lists.debian.org/debian-lts-announce/2019/04/msg00022.html","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST","x_transferred","web"]},{"url":"https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST","x_transferred","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2017-18078"},{"url":"https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b@%3Cissues.bookkeeper.apache.org%3E"},{"url":"https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4@%3Cissues.bookkeeper.apache.org%3E"},{"url":"https://github.com/advisories/GHSA-g2wx-phqf-j84q"},{"url":"https://security-tracker.debian.org/tracker/CVE-2017-18078","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2018/suse-su-20180546-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1057974","tags":["report"]},{"url":"https://bugzilla.suse.com/1068588","tags":["report"]},{"url":"https://bugzilla.suse.com/1071224","tags":["report"]},{"url":"https://bugzilla.suse.com/1071311","tags":["report"]},{"url":"https://bugzilla.suse.com/1075801","tags":["report"]},{"url":"https://bugzilla.suse.com/1077925","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2017-18078","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2017-18078","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2017-18078","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2016-10156","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-15908","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-9445","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-15686","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-15687","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-15688","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-16864","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-16865","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-21029","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-6954","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-20386","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-3842","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-3843","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-3844","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-6454","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-13529","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-1712","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-33910","tags":["web"]}],"sources":{"cve":[{"id":"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.","status":"published","published":"2018-01-29T05:00:00Z","modified":"2024-08-05T21:13:47.523Z","updated_at":"2026-11-02T14:33:22.064284Z"}],"euvd":[{"id":"EUVD-2017-9215","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.","status":"published","published":"2018-01-29T05:00:00Z","modified":"2024-08-05T21:13:47Z","updated_at":"2026-11-03T02:23:07.6199Z"}],"ghsa":[{"id":"GHSA-g2wx-phqf-j84q","title":"systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on...","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.","status":"published","published":"2022-05-13T01:04:10Z","modified":"2023-02-01T05:02:50Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T14:49:58.498747Z"}],"nvd":[{"id":"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.","status":"published","published":"2018-01-29T05:29:00.213Z","modified":"2026-06-17T01:12:09.83Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":4.6,"vector":"AV:L/AC:L/Au:N/C:P/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-59"],"updated_at":"2026-11-02T14:04:13.257031Z"}],"osv":[{"id":"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.","status":"published","published":"2018-01-29T05:29:00.213Z","modified":"2026-10-24T10:50:28.956319653Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:05.486486Z"},{"id":"DEBIAN-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.","status":"published","published":"2018-01-29T05:29:00.213Z","modified":"2026-09-01T20:03:46.951768782Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:29.100767Z"},{"id":"UBUNTU-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.","status":"published","published":"2018-01-29T05:29:00Z","modified":"2026-04-22T11:21:39.634205Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"},{"version":"3.0","score":7.8,"vector":"CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:14.977781Z"},{"id":"DLA-1762-1","title":"systemd - security update","status":"published","published":"2019-04-24T00:00:00Z","modified":"2026-03-09T01:20:54.480901Z","updated_at":"2026-11-02T15:46:09.777694Z"},{"id":"openSUSE-SU-2024:11420-1","title":"libsystemd0-249.4-2.2 on GA media","description":"These are all security issues fixed in the libsystemd0-249.4-2.2 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T02:45:22.858405Z","updated_at":"2026-11-02T16:58:35.195147Z"},{"id":"SUSE-SU-2018:0546-1","title":"Security update for systemd","description":"\n  \nThis update for systemd fixes the following issues:\n\nSecurity issue fixed:\n\n- CVE-2017-18078: tmpfiles: refuse to chown()/chmod() files which are\n  hardlinked, unless protected_hardlinks sysctl is on. This could be used\n  by local attackers to gain privileges (bsc#1077925)\n\nNon Security issues fixed:\n\n- core: use id unit when retrieving unit file state (#8038) (bsc#1075801)\n- cryptsetup-generator: run cryptsetup service before swap unit (#5480)\n- udev-rules: all values can contain escaped double quotes now (#6890)\n- strv: fix buffer size calculation in strv_join_quoted()\n- tmpfiles: change ownership of symlinks too\n- stdio-bridge: Correctly propagate error\n- stdio-bridge: remove dead code\n- remove bus-proxyd (bsc#1057974)\n- core/timer: Prevent timer looping when unit cannot start (bsc#1068588)\n\n- Make systemd-timesyncd use the openSUSE NTP servers by default\n  Previously systemd-timesyncd used the Google Public NTP servers\n  time{1..4}.google.com\n\n- Don't ship /usr/lib/systemd/system/tmp.mnt at all (bsc#1071224)\n  But we still ship a copy in /var.\n  Users who want to use tmpfs on /tmp are supposed to add a symlink in\n  /etc/ pointing to the copy shipped in /var.\n  To support the update path we automatically create the symlink if\n  tmp.mount in use is located in /usr.\n\n- Enable systemd-networkd on Leap distros only (bsc#1071311)\n\n","status":"published","published":"2018-02-26T15:35:50Z","modified":"2026-02-04T04:19:42.709699Z","updated_at":"2026-11-02T15:53:44.594517Z"}]}}