Detect CVE-2021-30952: Apple Multiple Products Integer Overflow Exploitation in Elastic Security
Detects exploitation attempts of CVE-2021-30952, an integer overflow vulnerability in Apple Multiple Products. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild. Integer overflow conditions in Apple platform components can lead to memory corruption, arbitrary code execution, or privilege escalation.
MITRE ATT&CK
Elastic Detection Query
sequence by host.name, user.name with maxspan=5m
[process where host.os.type == "macos"
and process.name in ("com.apple.WebKit.WebContent", "WebContent", "Safari", "MobileSafari")
and event.type == "start"]
[process where host.os.type == "macos"
and process.parent.name in ("com.apple.WebKit.WebContent", "WebContent", "Safari")
and process.name not in ("com.apple.WebKit.Networking", "com.apple.WebKit.GPU", "SafariCloudHistoryPushAgent")
and not process.executable : "/Applications/*"
and not process.executable : "/System/*"
and not process.executable : "/usr/bin/*"]EQL sequence rule detecting WebKit process spawning unexpected child processes outside standard Apple application paths, a behavioral indicator of post-exploitation following CVE-2021-30952 integer overflow.
Data Sources
Required Tables
False Positives & Tuning
- Custom enterprise applications that embed WebKit as a framework and spawn helpers
- Third-party browsers based on WebKit launching legitimate companion processes
- System integrity protection disabled on developer machines running non-standard builds
Other platforms for CVE-2021-30952
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Simulate WebKit Process Spawning Shell from Non-Standard Path
Expected signal: Process creation event showing /tmp/webkit-sim/WebContent spawning with process name matching WebContent but executing from /tmp path
- Test 2Create Persistence via LaunchAgent After Simulated WebKit Compromise
Expected signal: File creation event for plist in ~/Library/LaunchAgents/ followed by launchctl process execution loading the new agent
- Test 3Simulate Integer Overflow Memory Pressure via Safari Crash Report Generation
Expected signal: File creation event for .crash file in /tmp with WebContent prefix; potential file integrity monitoring alert
Unlock Pro Content
Get the full detection package for CVE-2021-30952 including response playbook, investigation guide, and atomic red team tests.