Malicious PDF — malware analysis report

Static analysis result for SHA-256 f2a3acaad94618a9…

MALICIOUS

PDF

83.0 KB Created: 2021-09-14 13:54:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: d4ed1983277ece7670c6818a9638efe0 SHA-1: bac57afd073036f63739cecc45b1543ebd646189 SHA-256: f2a3acaad94618a9fa4186e2a0d50887ed45b05531d1334d27147190d3fb7fef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many pointing to compromised or disposable hosting, suggesting a link farm designed to lure users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zlato-invest.cz/upload/files/91707583520.pdf In PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/78665660390.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/xusabopevofafadolal.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/vavapewutimu.pdfIn PDF document text
    • http://michalpavlicek.com/uploaded/file/24202015872.pdfIn PDF document text
    • https://tiemhoamo.tiemhoahaibara.com/data/dulieu/files/sozawibazidop.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130e03c1d6cc---10930604607.pdfIn PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/talijasovoretebokufa.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161364a7fcec64---34611888028.pdfIn PDF document text
    • http://abarappresentanze.it/userfiles/files/fajiwapuwuwomasejakejof.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/f199d29ae091de6438abeca9c7291480/1792990796.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/17102683408.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/9d6588f0115abe1b28a49ef087b4a5f6/7167239456.pdfIn PDF document text
    • https://ecotranslation.ca/upload/editor/file/nobizobumiru.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/vt1g2n8vqodbbvvgjg9n88pp1t/sidagutugosunixowaretopa.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/bebiridoviwit.pdfIn PDF document text
    • https://dorfadvertising.com/ckfinder/userfiles/files/39831871410.pdfIn PDF document text
    • http://cgl.lu/userfiles/files/lajarekuxij.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/45509915363.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/99f12bbe01d787c76d6676cc9519ce25/xojalefujetamurejevafipup.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/dujowuvesagifoxetipa.pdfIn PDF document text
    • https://srccaa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/difimatevoti.pdfIn PDF document text
    • https://ckmusicdesign.nl/userfiles/file/rusijajajezivuvomiwumi.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/24706176310.pdfIn PDF document text
    • https://webrekruit.com/php_codes/Scott/VieauAssociates/code/userfiles/file/79388358918.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=human+anatomy+and+physiology+practical+book+pdf+downloadPDF 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_off0000e1fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FC 16160 bytes
SHA-256: 4c7e89a8258c85eb97a41834bf703cc92017ef78600fab1ed06eb0c83d11816b
font_01_sfnt_off00010b6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012383.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12383 11456 bytes
SHA-256: a2e0adbce096a7ab631d3d7ea95c27a8eccf63e3a9de5432de055593fcd3297a