CVE-2017-18078
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…
Does this matter?
A public exploit is published in Exploit-DB and the impact is high, while EPSS rates exploitation at 1.1%. Anyone can run this; patch or mitigate before the next change window and check exposed instances for signs of use.
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.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.06% probability · 65th percentile
- Public exploits
- 1 in Exploit-DB · first 29 January 2018
- CISA KEV
- Not listed
- Weakness
- CWE-59
- Affected
- systemd project/systemd · debian/debian linux · opensuse/leap
- Source
- cve@mitre.org
EPSS 1.1% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
References
- http://lists.opensuse.org/opensuse-updates/2018-02/msg00109.htmlMailing List, Third Party Advisory
- http://packetstormsecurity.com/files/146184/systemd-Local-Privilege-Escalation.htmlExploit, Third Party Advisory, VDB Entry
- http://www.openwall.com/lists/oss-security/2018/01/29/3Exploit, Mailing List, Third Party Advisory
- https://github.com/systemd/systemd/issues/7736Exploit, Issue Tracking, Third Party Advisory
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2019/04/msg00022.htmlMailing List, Third Party Advisory
- https://www.exploit-db.com/exploits/43935/Exploit, Third Party Advisory, VDB Entry
- https://www.openwall.com/lists/oss-security/2018/01/29/4Mailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-updates/2018-02/msg00109.htmlMailing List, Third Party Advisory
- http://packetstormsecurity.com/files/146184/systemd-Local-Privilege-Escalation.htmlExploit, Third Party Advisory, VDB Entry
- http://www.openwall.com/lists/oss-security/2018/01/29/3Exploit, Mailing List, Third Party Advisory
- https://github.com/systemd/systemd/issues/7736Exploit, Issue Tracking, Third Party Advisory
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2019/04/msg00022.htmlMailing List, Third Party Advisory
- https://www.exploit-db.com/exploits/43935/Exploit, Third Party Advisory, VDB Entry
- https://www.openwall.com/lists/oss-security/2018/01/29/4Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.