Firefox Netmonitor Privilege Escalation Vulnerability (CVE-2026-4717)
CVE-2026-4717 is a critical privilege escalation vulnerability in the Netmonitor component of Firefox, Firefox ESR, and Thunderbird, potentially allowing an attacker to gain elevated privileges on a vulnerable system.
CVE-2026-4717 is a critical vulnerability affecting Mozilla Firefox, Firefox ESR, and Thunderbird. The vulnerability lies within the Netmonitor component and can lead to privilege escalation. Specifically, Firefox versions prior to 149, Firefox ESR versions prior to 140.9, Thunderbird versions prior to 149, and Thunderbird ESR versions prior to 140.9 are affected. The vulnerability allows an attacker to potentially gain elevated privileges on the targeted system. This could allow for arbitrary…
Detection coverage 2
Detect Exploitation Attempts of CVE-2026-4717 via Web Logs
highDetects potential exploitation attempts of CVE-2026-4717 based on suspicious HTTP requests targeting Firefox, Firefox ESR, or Thunderbird.
Detect Thunderbird Child Process Executing Suspicious Programs
mediumDetects Thunderbird spawning a child process running suspicious executables that may indicate exploitation
Detection queries are kept inside the platform. Get full rules →
Indicators of compromise
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