T1189 / ATT&CK

Windows Analytic 0498

Correlated evidence of anomalous browser/network behavior (suspicious external resource fetches and script injection patterns) followed by atypical child processes, ephemeral execution contexts, memory modification or process injection, and unexpected file drops. Defender sees network requests to previously unseen/suspicious domains or resources + browser process spawning unusual children or loading unsigned modules + file writes or registry changes shortly after those requests.

• WinEventLog:Security EventCode=4624, 4648
• WinEventLog:Security EventCode=4688
• WinEventLog:Sysmon EventCode=3, 22
• WinEventLog:Application Browser or plugin/application logs showing script errors, plugin enumerations, or unusual extension load events
• etw:Microsoft-Windows-Kernel-Process Memory Modification / Unmapped module load or suspicious RWX allocations in the process space of a browser process
• WinEventLog:Sysmon EventCode=11
• NSM:Flow http.request: HTTP requests and responses for specific script resources, unexpected content-types (application/octet-stream for script URLs), suspicious referrers, or obfuscated javascript resources

Linux Analytic 0499

Correlated evidence of browser or webview fetches to uncommon domains or mutated JS resources (proxy/NGFW logs + Zeek/HTTP logs) followed by unexpected interpreters or script engines executing (python, ruby, sh) spawned from browser processes or user sessions, rapid on-disk staging in /tmp, and outbound connections that deviate from baseline. Defender sees: uncommon resource fetch → short-lived child process executions from user browser context → file writes in temp directories → anomalous outbound C2-like connections.

• auditd:SYSCALL execve: execve calls where a browser/webview process is parent and child is interpreter (python, sh, ruby) or downloader (curl, wget)
• linux:syslog Application or browser logs (webview errors, plugin enumerations) indicating suspicious script evaluation or plugin loads
• NSM:Flow http::response: HTTP responses with suspicious content-type for scripts, long obfuscated javascript bodies, or redirects to exploit kit domains
• linux:Sysmon New files in /tmp, /var/tmp, $HOME/.cache, executed within TimeWindow after browser HTTP fetch
• NSM:Connections Outbound connections from newly spawned child processes or from the browser to uncommon endpoints or on anomalous ports

macOS Analytic 0500

Correlated evidence where Safari/Chrome/WebKit-based processes issue network requests for uncommon or obfuscated JS resources followed by spawning of script interpreters, launchd or ad-hoc binaries, unusual child processes, or dynamic library loads into browser processes. Defender sees: proxy/HTTP logs with suspicious resource content + unifiedlogs/ASL showing browser/plugin crashes or extension loads + process events indicating child process creation and file writes to /var/folders or /tmp shortly after the fetch.

• macos:unifiedlog Logs from unifiedlogging that show browser crashes, plugin enumerations, extension installs or errors around the same time as suspicious network fetches
• macos:unifiedlog process_create: Process creation where parent is Safari/Google Chrome and child is script interpreter or signed-but-unusual helper binary
• macos:unifiedlog New files written to /var/folders, /tmp, ~/Library/Caches, or ~/Downloads by browser context or its children
• NSM:Flow HTTP/HTTPS requests for script resources flagged by content inspection (excessive obfuscation, eval usage, unusual redirects)
• macos:unifiedlog Anomalous dyld dynamic library loads or RWX memory mappings in browser process

Identity Provider Analytic 0501

Post-compromise identity & session anomalies that follow a drive-by compromise: token reuse from new/unfamiliar IPs, anomalous sign-in patterns for previously inactive users, unexpected consent/grant events, or provisioning changes. Defender sees an endpoint/browser compromise (network + endpoint signals) followed by unusual IdP events: new refresh token issuance, consent/consent-grant events, odd MFA bypass patterns, or unusual OAuth client registrations.

• azure:signinlogs SignIn: Sign-ins flagged as atypical (new geographic region, unfamiliar device id) shortly after correlated endpoint/browser compromise times
• m365:unified Application Consent grants, new OAuth client registrations, or unusual admin-level activities executed by a user account shortly after suspected drive-by compromise
• saas:auth Refresh token issuance or refresh token usage from new IPs or user agents
• AWS:CloudTrail ConsoleLogin: If IdP backed by cloud provider, Console login from new IP/agent after correlated endpoint compromise