CVE-2021-29945 Null dereference in Firefox

What is CVE-2021-29945?

CVE-2021-29945 is a medium-severity vulnerability in Mozilla Firefox, published on 24 Jun 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

The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and result in a crash. *Note: This issue only affected x86-32 platforms. Other platforms are unaffected.*. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

Weakness: CWE-682

Which versions are affected by CVE-2021-29945?

It affects 3 products.

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

How do I fix CVE-2021-29945?

Upgrade to a fixed version.

Is CVE-2021-29945 being exploited?

There is no known exploitation of CVE-2021-29945 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-2021-29945, GHSA-79cg-jg39-89hq, UBUNTU-CVE-2021-29945.