CVE-2018-6954

Severity Score

7.8

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

systemd-tmpfiles in systemd through 237 mishandles symlinks present in non-terminal path components, which allows local users to obtain ownership of arbitrary files via vectors involving creation of a directory and a file under that directory, and later replacing that directory with a symlink. This occurs even if the fs.protected_symlinks sysctl is turned on.

systemd-tmpfiles en systemd, hasta 237, gestiona de manera incorrecta los vínculos simbólicos presentes en componentes de ruta no terminales. Esto permite que usuarios locales se hagan dueños de archivos arbitrarios mediante vectores relacionados con la creación de un directorio y un archivo bajo ese directorio para, posteriormente, reemplazarlo por un vínculo simbólico. Esto ocurre incluso aunque el sysctl fs.protected_symlinks esté activado.

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2018-02-13 CVE Reserved
2018-02-13 CVE Published
2023-03-08 EPSS Updated
2024-08-05 CVE Updated
2024-08-05 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-59: Improper Link Resolution Before File Access ('Link Following')

CAPEC

References (6)

URL	Tag	Source
https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E	Mailing List
https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E	Mailing List

URL	Date	SRC
https://github.com/systemd/systemd/issues/7986	2024-08-05

URL	Date	SRC

URL	Date	SRC
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00062.html	2023-11-07
https://usn.ubuntu.com/3816-1	2023-11-07
https://usn.ubuntu.com/3816-2	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Systemd Project Search vendor "Systemd Project"		Systemd Search vendor "Systemd Project" for product "Systemd"				<= 237 Search vendor "Systemd Project" for product "Systemd" and version " <= 237"		-		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				16.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				18.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "18.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				18.10 Search vendor "Canonical" for product "Ubuntu Linux" and version "18.10"		-		Affected
Opensuse Search vendor "Opensuse"		Leap Search vendor "Opensuse" for product "Leap"				42.3 Search vendor "Opensuse" for product "Leap" and version "42.3"		-		Affected