Omar Ahmed

24 papers A 3B 1Journal 14Unranked 6
YearRankTypeTitle / Venue / Authors
2026 J jnl
IACR Cryptol. ePrint Arch.
Omar Ahmed, Nektarios Georgios Tsoutsos
2025 J jnl
CoRR
Mostafa A. Mostafa, Mohamed Khaled, Abdelrahman Ali, Amr Mostafa, Mariam Mohamed, Omar Ahmed, Osama Khalil
2024 A conf
DATE
Patrick Schmidt, Iuliia Topko, Matthias Stammler, Tanja Harbaum, Jürgen Becker, Rico Berner, Omar Ahmed, Jakub Jagielski, Thomas Seidler, Markus Abel, Marius Kreutzer, Maximilian Kirschner, Victor Pazmino Betancourt, Robin Sehm, Lukas Groth, Andrija Neskovic, Rolf Meyer, Saleh Mulhem, Mladen Berekovic, Matthias Probst, Manuel Brosch, Georg Sigl, Thomas Wild, Matthias Ernst, Andreas Herkersdorf, Florian Aigner, Stefan Hommes, Sebastian Lauer, Maximilian Seidler, Thomas Raste, Gasper Skvarc Bozic, Ibai Irigoyen Ceberio, Muhammad Hassan, Albrecht Mayer
2024 A conf
ECAI
Omar Ahmed, Mihai Oproescu, Gabriel-Vasile Iana
2024 J jnl
IEEE Access
Omar Ahmed, Charles Gouert, Nektarios Georgios Tsoutsos
2024 J jnl
IACR Cryptol. ePrint Arch.
Omar Ahmed, Nektarios Georgios Tsoutsos
2023 J jnl
CoRR
Abdelrahman Boda Sadallah, Omar Ahmed, Shimaa Mohamed, Omar Hatem, Doaa Hesham, Ahmed H. Yousef
2023 J jnl
CoRR
Mohd Ashhad, Omar Ahmed, Sooraj K. Ambat, Zeeshan Ali Haq, Mansaf Alam
2023 A conf
ECAI
Mihai Oproescu, Omar Ahmed, Gabriel-Vasile Iana, Maria Magdalena Dicu, Ancuta Mihaela Balteanu, Monica Baldea
2020 J jnl
IEEE Access
Omar Ahmed, Fuji Ren, Ammar Hawbani, Yaser Al-Sharabi
2018 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Robert Collier, Gary William Grewal
2018 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Gary Gréwal
2018 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Karanvir Chattha, Ben Kelly
2017 conf
ICM
Dunia Jamma, Omar Ahmed, Shawki Areibi, Gary Gréwal
2016 conf
ICM
Dunia Jamma, Omar Ahmed, Shawki Areibi, Gary Gréwal, Nicholas Molloy
2016 conf
CAMAD
Mohammed Elmahgiubi, Omar Ahmed, Shawki Areibi, Gary Gréwal
2015 conf
ICECS
Ahmed El-Samman, Omar Ahmed, Stefano Gregori
2013 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Robert Collier, Gary William Grewal
2013 conf
ReConFig
Omar Ahmed, Shawki Areibi
2013 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Gary William Grewal
2012 J jnl
VLSI Design
Maxwell Walton, Omar Ahmed, Gary William Grewal, Shawki Areibi
2011 B conf
IWCMC
Omar Ahmed, Shawki Areibi
2011 J jnl
Int. J. Reconfigurable Comput.
Omar Ahmed, Shawki Areibi, Karanvir Chattha, Ben Kelly
2010 conf
AlgoSyn
Omar Ahmed
redb/extractors/pe_extractors/pe_overlay.py
← Index redb/extractors/pe_extractors/pe_overlay.py python
from hashlib import md5, sha1, sha256
import inspect
from datetime import datetime, timezone
from typing import Any

import magic
from magika import Magika

from redb.extractors.enum import Tag
from redb.extractors.pe_extractor import PEExtractor
from redb.models.dataclasses import PEOverlay


class PEOverlayExtractor(PEExtractor):

    def __init__(
        self,
        filepath,
        log,
        exporters=None,
        index_prefix=None,
        elastic_index=None,
        known_benign=False,
        known_malicious=False,
        pe=None,
    ):
        super().__init__(
            filepath,
            log,
            exporters,
            index_prefix,
            elastic_index,
            known_benign,
            known_malicious,
            pe,
        )
        self.elastic_index = self.index_prefix + "-pe_overlay"
        self.log.debug(inspect.currentframe().f_code.co_name)

    def tag(self):
        return Tag.PE_OVERLAY.value

    def _extract_pe_overlay(self):
        self.log.debug(inspect.currentframe().f_code.co_name)
        overlay = self.pe.get_overlay()
        if overlay:
            return PEOverlay(
                _id=sha256(overlay).hexdigest(),
                overlay_size=len(overlay),
                overlay_entropy=self.calculate_entropy(overlay),
                overlay_offset=self.pe.get_overlay_data_start_offset(),
                overlay_mimetype=magic.from_buffer(overlay, mime=True),
                overlay_type=magic.from_buffer(overlay),
                overlay_magika=Magika().identify_bytes(overlay).output.ct_label,
                overlay_sha256=sha256(overlay).hexdigest(),
                overlay_sha1=sha1(overlay).hexdigest(),
                overlay_md5=md5(overlay).hexdigest(),
            )
        return None

    def extract(self):
        try:
            self.log.debug(inspect.currentframe().f_code.co_name)
            overlay = self._extract_pe_overlay()
            # self.export_to_elastic([overlay])  # Let the exporters handle this
            return overlay
        except Exception as e:
            self.log.error(f"Error extracting PE overlay: {e}")
            return None

    def prepare_export_data(self, exporter_type: str) -> Any:
        if exporter_type == "ElasticsearchExporter":
            return self.extract()
        elif exporter_type == "ClickHouseExporter":
            overlay = self.extract()
            if overlay is None:
                return None
            
            data = []
            current_time = datetime.now(timezone.utc)
            
            data.append([
                self.sha256,              # sha256
                self.md5,                 # md5
                self.sha1,                # sha1
                overlay.overlay_size,     # overlay_size
                overlay.overlay_entropy,  # overlay_entropy
                overlay.overlay_offset,   # overlay_offset
                overlay.overlay_mimetype, # overlay_mimetype
                overlay.overlay_type,     # overlay_type
                overlay.overlay_magika,   # overlay_magika
                overlay.overlay_sha256,   # overlay_sha256
                overlay.overlay_sha1,     # overlay_sha1
                overlay.overlay_md5,      # overlay_md5
                current_time             # analysis_date
            ])
            
            column_names = [
                'sha256', 'md5', 'sha1', 'overlay_size', 'overlay_entropy',
                'overlay_offset', 'overlay_mimetype', 'overlay_type', 'overlay_magika',
                'overlay_sha256', 'overlay_sha1', 'overlay_md5',
                'analysis_date'
            ]
            
            if not data:
                return None

            column_type_names = [
                'FixedString(64)', 'FixedString(32)', 'FixedString(40)',
                'UInt64', 'Float64', 'UInt64',
                'LowCardinality(String)', 'LowCardinality(String)', 'LowCardinality(String)',
                'FixedString(64)', 'FixedString(40)', 'FixedString(32)',
                'DateTime64(3, \'UTC\')'
            ]

            return (data, column_names, column_type_names)

    def get_clickhouse_table(self) -> str:
        return "redb_pe_overlays"