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

Vulnerability identifier: #VU46963

CSH Severity: Low

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

CVE-ID: CVE-2020-15677

CWE-ID: CWE-451

Exploitation vector: Remote access

Exploit availability: No public exploit available

Affected software:
Firefox ESR
Mozilla Firefox
Arch Linux
Gentoo Linux
Red Hat Enterprise Linux for Power, big endian
Red Hat Enterprise Linux for Scientific Computing
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux Server
Red Hat Enterprise Linux Workstation
Red Hat Enterprise Linux Desktop
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux Server - TUS
Slackware Linux
Opensuse
Ubuntu
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions
firefox (Alpine package)
thunderbird (Red Hat package)
firefox-esr (Alpine package)
firefox (Red Hat package)
firefox-esr (Debian package)
thunderbird (Debian package)
firefox (Ubuntu package)
Mozilla Thunderbird

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.

Install updates from vendor's website.

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