CVE-2023-29535 Use after free in Firefox

What is CVE-2023-29535?

CVE-2023-29535 is a medium-severity use after free vulnerability in Mozilla Firefox, published on 2 Jun 2023. 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

Following a Garbage Collector compaction, weak maps may have been accessed before they were correctly traced. This resulted in memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 112, Focus for Android < 112, Firefox ESR < 102.10, Firefox for Android < 112, and Thunderbird < 102.10.

Which versions are affected by CVE-2023-29535?

It affects 5 products.

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

How do I fix CVE-2023-29535?

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-2023-29535 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-29535 exists.

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-2023-29535, GHSA-6w79-w79x-722p, UBUNTU-CVE-2023-29535.