#VU7078 Privilege escalation in Firefox ESR - CVE-2017-7767

Vulnerability identifier: #VU7078

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-7767

CWE-ID: CWE-20

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Firefox ESR
Client/Desktop applications / Web browsers

Vendor: Mozilla

Description
The vulnerability allows a local attacker to gain elevated privileges on the target system.

The vulnerability exists in the Mozilla Maintenance Service on Windows due to improper input validation. A local attacker can overwrite arbitrary files with junk data using the Mozilla Windows Updater and gain system privileges.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation
Update to version 52.2.

Vulnerable software versions

Firefox ESR: 38.0 - 38.8.0, 45.0 - 45.8, 52.0.1

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2017-16/

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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.