Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9d597e76f0ae3fa…

MALICIOUS

PDF

66.8 KB Created: 2021-09-22 23:58:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a782f304778ea79cd91ba3cd68d3e42e SHA-1: dd6d35668e44e551ae49fee73c1940486b69669e SHA-256: a9d597e76f0ae3faa88ab49d94fa4ec5162892c92154b6f57678169e79f5f85b
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable hosting and are structured as link farms, a common tactic for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, suggesting the PDF's primary purpose is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9524

Heuristics 4

  • 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
  • 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://chcial.ru/uplcv?utm_term=palm+store+vs+play+store
    • http://short-story.ru/upload/file/86268038096.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/161400d2dd6447---nibisaxetafu.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614b6dddea2a4---fevasuzojobudiw.pdf
    • http://uklearningnetwork.com/userfiles/file/fazedijezuterabef.pdf
    • https://www.larche-de-jules.fr/ckfinder/userfiles/files/fedixudorapexijurode.pdf
    • https://behagi.eus/files/galeria/files/wunojupulanas.pdf
    • http://bjerkelunden.org/content/files/userfiles/file///jexewegekuweteraw.pdf
    • http://argol-editions.fr/userfiles/file/berovobubowilawoku.pdf
    • http://bielwod.com/userfiles/file/97588164137.pdf
    • http://proclima-membranes.ru/userfiles/file/64517046137.pdf
    • http://residencecarlofelice.com/userfiles/files/tapidejobagevaf.pdf
    • http://mygiftltd.com/userfiles/file/nobidalovesobubejune.pdf
    • https://bdlvn.com/steel/upload/files/2692527624.pdf
    • http://tobn56.com/UpFiles/file/5183265026.pdf
    • http://supair-lux.hu/ckfinder/userfiles/files/19288779522.pdf
    • http://mirai-kankyo.com/userfiles/files/sonikevisibifigalopupenug.pdf
    • http://offerseir.com/basefile/offerseircom/files/duvupezuxax.pdf
    • https://shoppingplanet.ro/ckfinder/userfiles/files/42724001302.pdf
    • https://clubforeducation.com/FCKeditor/userfiles/file/63639160659.pdf
    • http://bouwbedrijfansing.nl/userfiles/file/36791912870.pdf
    • http://moscowfashion.net/content/xuploadimages/file/sowak.pdf
    • http://www.ekoforte.com/upload/file/gasonexibisuwir.pdf
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7e9.bin
3a6ce1cf87d49c836e6e443a618b7ab522227d7b372326dcef32a5c42b92a2dd
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E9 10400 bytes