Vulnerability Spotlight: Code execution vulnerability in Mozilla Firefox
Summary: Cisco Talos's Marcin "Icewall" Noga discovered a use-after-free vulnerability, TALOS-2021-1345 (CVE-2021-29985), in Mozilla Firefox's nsBufferedStream component, part of the browser's Stream buffering functionality. An attacker who tricks a user into visiting a specially crafted malicious web page could trigger a race condition leading to the use-after-free and potential remote code execution, and Talos confirmed Firefox version 89.0.3 x64 could be exploited.
Key Takeaway: The flaw sits in a widely used browser on many operating systems and requires only that a user visit a malicious page, so unpatched Firefox 89.0.3 x64 endpoints remain exposed until updated; Talos's Snort rules 57969 and 57970 detect exploitation attempts.
Read the original at Cisco Talos ↗
- Topics
- Vulnerabilities & Patching
- Mentions
- CVE-2021-29985
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