CVE-2021-23984 Other in Firefox

What is CVE-2021-23984?

CVE-2021-23984 is a medium-severity vulnerability in Mozilla Firefox, published on 31 Mar 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Weakness: CWE-290

Which versions are affected by CVE-2021-23984?

It affects 3 products.

Products include Mozilla Firefox, Mozilla Firefox Esr, Mozilla Thunderbird.

How do I fix CVE-2021-23984?

Upgrade to a fixed version.

Is CVE-2021-23984 being exploited?

There is no known exploitation of CVE-2021-23984 in the wild and no public exploit code.

Other vulnerabilities in Mozilla Firefox

• CVE-2019-11708 Mozilla Firefox and Thunderbird Sandbox Escape Exploited Critical 10.0
• CVE-2010-3765 Mozilla Multiple Products Remote Code Execution Exploited Critical 9.8
• CVE-2022-26486 Mozilla Firefox Use-After-Free Exploited Critical 9.6
• CVE-2022-26485 Mozilla Firefox Use-After-Free Exploited High 8.8
• CVE-2019-11707 Mozilla Firefox and Thunderbird Type Confusion Exploited High 8.8

All Mozilla Firefox vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-23984, GHSA-5cpw-36f2-hgw7, UBUNTU-CVE-2021-23984.