Spoofing attack in Mozilla Firefox and Firefox ESR - CVE-2020-15677

Detailed vulnerability description

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to way Firefox displays name of the data origin when downloading files. A remote attacker can spoof origin of the downloaded file and display the name of the intermediate website instead of the original source name.

Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack but requires that the spoofed website has an open redirect vulnerability.

How to mitigate CVE-2020-15677

Sources

• https://www.mozilla.org/en-US/security/advisories/mfsa2020-42/
• https://www.mozilla.org/en-US/security/advisories/mfsa2020-43/