CVE-2018-6557

The MOTD update script in the base-files package in Ubuntu 18.04 LTS before 10.1ubuntu2.2, and Ubuntu 18.10 before 10.1ubuntu6 incorrectly handled temporary files. A local attacker could use this issue to cause a denial of service, or possibly escalate privileges if kernel symlink restrictions were disabled.

CVSS v3.0 7.0 HIGH
CVSS v2.0 4.4 MEDIUM

7.0^/10

CVSS v3.0 : HIGH

Vector : AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 3.4 / Impact : 6.4

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://usn.ubuntu.com/3748-1/	Vendor Advisory
http://www.securitytracker.com/id/1041530	VDB Entry Third Party Advisory
http://www.securityfocus.com/bid/105148	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:18.10:::::::*
	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::

Information

Published : 2018-08-21 16:29

Updated : 2018-11-21 18:15

NVD link : CVE-2018-6557

Mitre link : CVE-2018-6557

JSON object : View

Products Affected

canonical

ubuntu_linux

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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