Malicious PDF — malware analysis report

Static analysis result for SHA-256 6331341bf8c5211c…

MALICIOUS

PDF

91.1 KB Created: 2021-06-16 18:36:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 65b8831ae8d86f9d3d396e9ef81daad8 SHA-1: d614e4245c73e99ce1c5066233833e1cdf03e752 SHA-256: 6331341bf8c5211cce879de3ce42e29dfb76440c73c78be56923fe90d4165bb0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a phishing lure. It contains numerous links, many pointing to compromised WordPress sites and disposable domains, suggesting an attempt to redirect users to malicious content or download further payloads. The document body, though heavily obfuscated, appears to be a disguise for a solution manual to encourage downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://queure.ru/uplcv?utm_term=solution+manual+cost+accounting+horngren+15th+edition+pdf PDF link annotation
    • https://laplacedesstores.com/upload/file/82347388321.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/2828c860626aa3910227ad51e0c31974/74005978329.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608742535cadf---butejaxukomek.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a471cf81cf9---gexusafakuremovopafawa.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16094cfb2ee7cb---dovejeveligobado.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/32g23f760calct74v193baqpdq/60924397454.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/xidofadagugukowulureve.pdfIn PDF document text
    • https://bursac.net/userfiles/file/vijenenek.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16095da1cbc0b2---dabufobi.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/c9ca72b780923c279772f5291170ed0b/42427294539.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608f21cd8b187---fiwotojadupafo.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/17878111773.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/l9v8814i75qgrdu6eu5pfm9h6k/beletineromoze.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/uhjhijnell4034qo75g4ggr4hr/lizegekizuv.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160a35fde58fe8---54207546901.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfc21b661b---41372194697.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/tipobeb.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160a318bc48411---6688461148.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_off00012392.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12392 5848 bytes
SHA-256: 64d964e641786cb016efe1fc1d69f10c8a04e09bbeb9c6a01bf7a1c01213ec8b
font_01_sfnt_off0001374d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1374D 11540 bytes
SHA-256: 37b0986c39ac2895b18c0eb1742bae3af0a98886cd661481cf7cc958bfd0f42f