#VU32904 Insecure DLL loading in Mozilla Firefox and Firefox ESR

Published: 2020-07-29

Vulnerability identifier: #VU32904

Vulnerability risk: Low

CVSSv3.1: 7.1 [CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-15657


Exploitation vector: Local

Exploit availability: No

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

Vendor: Mozilla


The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the application loads DLL libraries in an insecure manner from the installation directory. A remote attacker can place a specially crafted .dll file into directory, from which Firefox is being installed, trick the victim into launching the Firefox installer and execute arbitrary code on the system.

Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 70.0 - 78.0.2

Firefox ESR: 78.0 - 78.0.2

External links

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.

Latest bulletins with this vulnerability