Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d99b7588bf21545…

MALICIOUS

PDF

81.0 KB Created: 2021-08-14 23:22:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c167867ff4d45f71a039a37b959e5ac5 SHA-1: 1850f698e33c2ee11d2f017e6617f65df81eafc4 SHA-256: 0d99b7588bf21545b1aa7f1c3e8a4b9cb9736b614371f48190bf44a0da0b100d
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting domains. The presence of external URIs and the overall structure suggest an attempt to lure users to malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://huntic.ru/uplcv?utm_term=maths+olympiad+past+papers+grade+10+sinhala+pdf PDF link annotation
    • https://rivnerun.club/images/files/zigulizalibabu.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/mavinifo.pdfIn PDF document text
    • https://rozgarnetwork.com/ckfinder/userfiles/files/45224497891.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/54ca46e3fa0e241bb3349077778b9bbc/mawamil.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/momokel.pdfIn PDF document text
    • https://hoya.hr/UserFiles/file/fimemojipesazakadowafit.pdfIn PDF document text
    • https://healthmatters.me/userfiles/file/tudasuvojozifexev.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160f2150daa306---sumiraxazu.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/5cf3802f5a53c70af476718ae0295ea6/xezerikavefupudozuxabad.pdfIn PDF document text
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/70588409263.pdfIn PDF document text
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/71395352749.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c90939c02---91206475560.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/ne7em7s7lpmm1q2oqpka0dce76/66340299652.pdfIn PDF document text
    • https://steklo-shik.ru/userfiles/file/dumokakutebidavobituvima.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/daworasukaxugaxolug.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a9db9e399cf---vunigaminovenub.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/jemekepidaluvigel.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents//files/46833649175.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/zopofonazaradeg.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/newekulur.pdfIn PDF document text
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/99198966330.pdfIn PDF document text
    • http://abwrva.com/uploads/files/zupadofodusajusedeja.pdfIn PDF document text
    • 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_off0000d91b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f12d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12D 16644 bytes
SHA-256: 335ad9660dafed988766c897ccda007e86278f455cb1310298e502878dd073f5
font_02_sfnt_off00011c69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C69 11224 bytes
SHA-256: 0d84f9faa7ecfd7e489f3d251235798165a06e5c5448920ed95e51fbf1d4ab90