Malicious PDF — malware analysis report

Static analysis result for SHA-256 df33fa1954749703…

MALICIOUS

PDF

70.8 KB Created: 2021-05-28 17:15:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 569063efaccaac84241512cea116f46b SHA-1: 43a026986171dc4ea630080d063e37d7027f16be SHA-256: df33fa195474970372bce072d82790a3231fbbb7e756d7f44b9a79923c0e9aef
164 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The presence of a 'download button' heuristic further supports the idea that the document is designed to trick users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://wastran.ru/uplcv?utm_term=integrated+chinese+level+2+4th+edition+pdf PDF link annotation
    • http://strahovka66.ru/userfiles/file/46827217044.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160986956c8f4a---44929470908.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d197008924---93822936380.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f16f0f369---pilenogojavexujeziwe.pdfIn PDF document text
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/7cdf379d33b2b30ac0ff5f09c726d5cd/zitafezenuwoxigonobapa.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/22059361296.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/bofejomudumupa.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/446162d9d5f91b7e7823715f8cbeefa5/38293500821.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/nuzuwabugerololotin.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/d2c3c09a5e4131d2c74d3116dc5394ce/jonapebuxoguzarapepap.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/d59175a3e5d95bf47710e4a6121a3d68/lerezasakunudil.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/tibadipafar.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/kimedigukusakopuzabenopu.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608d62bb94326---45299483079.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609504de5d453---77030457090.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/6843dbd8f79aed30c5c88bdc7128c855/nofibugejafezidotiwifam.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A9 5632 bytes
SHA-256: d367e58cf7329a6e20cf2ec8812bb21b10431939c31adf5780d592eb56f4e49a
font_01_sfnt_off0000eae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE0 10416 bytes
SHA-256: a299f56b896820ac358ebf8b8b81d3adb3b8557251333e7083cba5a879423b1d