CVE-2021-43535 : What You Need to Know
Discover how a use-after-free vulnerability in Firefox, Thunderbird, and Firefox ESR could lead to memory corruption and crashes. Learn about impacted versions and mitigation steps.
A use-after-free vulnerability in Firefox, Thunderbird, and Firefox ESR could lead to memory corruption and potential crashes.
Understanding CVE-2021-43535
What is CVE-2021-43535?
A use-after-free vulnerability occurred when releasing an HTTP2 session object on a different thread, impacting Firefox < 93, Thunderbird < 91.3, and Firefox ESR < 91.3.
The Impact of CVE-2021-43535
The vulnerability could result in memory corruption and potentially exploitable crashes in affected applications.
Technical Details of CVE-2021-43535
Vulnerability Description
A use-after-free issue in the HTTP2 session object, impacting Firefox, Thunderbird, and Firefox ESR.
Affected Systems and Versions
- Firefox < 93
- Thunderbird < 91.3
- Firefox ESR < 91.3
Exploitation Mechanism
The vulnerability could be exploited through a crafted HTTP2 session object, leading to memory corruption.
Mitigation and Prevention
Immediate Steps to Take
- Update Firefox and Thunderbird to versions 93 and 91.3, respectively.
- Consider blocking malicious HTTP2 traffic.
Long-Term Security Practices
- Regularly update software to the latest versions.
- Maintain vigilance on security advisories from vendors.
Patching and Updates
Apply patches released by Mozilla for Firefox, Thunderbird, and Firefox ESR.