Pe Sieve

Overview

Pe Sieve is a proactive detection tool that appears across threat hunting workflows in this knowledge base. It is referenced as part of higher-level security analysis, investigation, monitoring, or validation activity rather than as an end in itself.

What It Is

Pe Sieve is best understood as a threat-hunting tool in this knowledge base. Its role is conceptual and system-facing rather than procedural: it gives analysts or defenders a structured way to examine evidence, model system behavior, or reason about security state.

How It Works

Pe Sieve works by turning technical inputs into more interpretable outputs at the system level. Across the source skills, it appears as part of larger analysis, investigation, monitoring, or validation loops rather than as a standalone end state.

Core Concepts

• threat hunting
• mitre attack
• dll sideloading
• defense evasion
• t1574
• edr
• proactive detection
• process hollowing
• process injection
• t1055
• malware
• detection

Typical Workflow

• 1. Identify Sideloading Targets: Research known vulnerable applications that load DLLs without full path qualification (LOLBAS, DLL-sideload databases).
• 2. Monitor DLL Load Events: Query Sysmon Event ID 7 for DLL loads where the DLL path differs from the application's expected directory.
• 3. Check DLL Signatures: Flag unsigned or untrusted DLLs loaded by signed executables.
• 4. Detect Path Anomalies: Identify legitimate executables running from unusual locations (Temp, AppData, Public) that may be decoy wrappers.
• 5. Hash Verification: Compare loaded DLL hashes against known-good versions and threat intel feeds.
• 6. Correlate with Process Behavior: Check if the host process exhibits unusual behavior (network connections, child processes) after loading the suspicious DLL.
• 7. Document and Remediate: Report sideloading instances, quarantine malicious DLLs, and update detection rules.
• 1. Understand Hollowing Mechanics: Process hollowing involves creating a legitimate process in suspended state, unmapping its memory, writing malicious code, then resuming execution.
• 2. Monitor Suspended Process Creation: Hunt for processes created with CREATE_SUSPENDED flag followed by memory writes and thread resumption.
• 3. Detect Memory Section Anomalies: Identify processes where the in-memory image differs from the on-disk binary (image mismatch).

Use Cases

• When investigating potential DLL hijacking in enterprise environments
• After EDR alerts on unsigned DLLs loaded by signed applications
• When hunting for APT persistence using legitimate application wrappers
• During incident response to identify trojanized applications
• When threat intel indicates DLL sideloading campaigns targeting specific software
• When investigating suspected fileless malware or in-memory threats
• After EDR alerts on process injection or suspicious memory operations
• When hunting for defense evasion techniques in a compromised environment
• When threat intel reports indicate process hollowing in active campaigns
• During purple team exercises validating T1055.012 detection coverage

Limitations

• Output still depends on context, data quality, and surrounding analysis.
• The tool should be interpreted as part of a broader workflow, not as a complete answer by itself.
• Capabilities and visibility vary depending on environment, integrations, and available inputs.

Related Tools

• Process Hacker, Sysmon, Volatility, API Monitor, CrowdStrike Falcon, Hollows Hunter, Microsoft Defender For Endpoint, And Hollowing

Sources

• detecting-dll-sideloading-attacks
• detecting-process-hollowing-technique
• detecting-process-injection-techniques
• detecting-t1055-process-injection-with-sysmon