CVE-2012-1940 Use after free in n/a

What is CVE-2012-1940?

CVE-2012-1940 is a critical use after free vulnerability in Mozilla Firefox, published on 5 Jun 2012. 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

Use-after-free vulnerability in the nsFrameList::FirstChild function in Mozilla Firefox 4.x through 12.0, Firefox ESR 10.x before 10.0.5, Thunderbird 5.0 through 12.0, Thunderbird ESR 10.x before 10.0.5, and SeaMonkey before 2.10 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption and application crash) by changing the size of a container of absolutely positioned elements in a column.

Weakness: CWE-399

Which versions are affected by CVE-2012-1940?

It affects 4 products.

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

How do I fix CVE-2012-1940?

Upgrade to a fixed version.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2012-1940 being exploited?

There is no known exploitation of CVE-2012-1940 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 GHSA-rqvr-fvm8-wh8c.