#VU11502 Race condition in screen-resolution-extra (Ubuntu package) - CVE-2018-8885

Vulnerability identifier: #VU11502

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-8885

CWE-ID: CWE-362

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
screen-resolution-extra (Ubuntu package)
Operating systems & Components / Operating system package or component

Vendor: Canonical Ltd.

Description
The vulnerability allows a local attacker to bypass security restrictions on the target system.

The weakness exists in screenresolution-mechanism due to improper use of the PolicyKit D-Bus API. A local attacker can trigger race condition via a setuid or pkexec process that is mishandled in a PolicyKitService._check_permission call and bypass security restrictions.

Mitigation
Install update from vendor's website.

Vulnerable software versions

screen-resolution-extra (Ubuntu package): 0.17.2

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External links
https://usn.ubuntu.com/3607-1/

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.