Malicious PDF — malware analysis report

Static analysis result for SHA-256 13eff84c7a4ebdd7…

MALICIOUS

PDF

80.5 KB Created: 2021-09-19 12:55:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: bc7650abed3fc6712a7a5afc86c09c0c SHA-1: 2f142eae7b7832497c58f3037fda88cf41599024 SHA-256: 13eff84c7a4ebdd7179e8310794f38344353c1b5d29dac95127e3129a1edd36f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with high confidence. It contains numerous embedded URLs pointing to a link farm hosted on various domains, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the final destination through a large number of distinct hosts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://texasbordervolunteers.org/userfiles/file/bajabodiloxoxezogomejogig.pdf In PDF document text
    • https://marathonroller.com/userfiles/files/ponok.pdfIn PDF document text
    • http://bindashnews.com/userfiles/file/gulakuxekek.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/27895554078.pdfIn PDF document text
    • https://eguiders.com/uploads/94046981905.pdfIn PDF document text
    • http://topmebli.com/content/xuploadimages/file/golojataxudu.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/53853399235.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/18684315614.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/24492267355.pdfIn PDF document text
    • https://serpavenger.com/ckfinder/userfiles/files/38665045554.pdfIn PDF document text
    • https://cansandientu.net/Images_upload/files/toluduzegegepegugi.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/mutupume.pdfIn PDF document text
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/1311984941.pdfIn PDF document text
    • http://sino-web.net/filespath/files/20210913032016.pdfIn PDF document text
    • http://peter-crooks.com/userfiles/file/22582856078.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/ucobbv3usk9pmotglaal68kg47/44281809943.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/dajiwilafebunivegata.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/13468309559.pdfIn PDF document text
    • http://strandedtattoo.net/file/nomoguzowozelapes.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/dunokijarowezotedabuwu.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021091975822_855930432.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/25805002635.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/52225884275.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=operations+management+pdf+heizerPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d47d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47D 17784 bytes
SHA-256: 365a0d630e1c3a9dadb20bc05a5756dcbec09638f9fc6f271460d92a5a8999b9
font_01_sfnt_off000102f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B07 10984 bytes
SHA-256: ba303c42cee9a9e03e16834762acf63aa3f7e4ae21f008018a4490da7c90ccc3