Mozilla has revealed that a critical security flaw impacting Firefox and Firefox Extended Support Release (ESR) has come under active exploitation in the wild.
The vulnerability, tracked as CVE-2024-9680, has been described as a use-after-free bug in the Animation timeline component.
“An attacker was able to achieve code execution in the content process by exploiting a use-after-free in Animation timelines,” Mozilla said in a Wednesday advisory.
“We have had reports of this vulnerability being exploited in the wild.”
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Security researcher Damien Schaeffer from Slovakian company ESET has been credited with discovering and reporting the vulnerability.
The issue has been addressed in the following versions of the web browser
- Firefox 131.0.2
- Firefox ESR 128.3.1, and
- Firefox ESR 115.16.1.
There are currently no details on how the vulnerability is being exploited in real-world attacks and the identity of the threat actors behind them.
That said, such remote code execution vulnerabilities could be weaponized in several ways, either as part of a watering hole attack targeting specific websites or by means of a drive-by download campaign that tricks users into visiting bogus websites.
Users are advised to update to the latest version to stay protected against active threats.