Malicious PDF — malware analysis report

Static analysis result for SHA-256 420a849717f01a1e…

MALICIOUS

PDF

90.1 KB Created: 2021-09-15 19:59:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 09e95755dd18d8e1fec958ff050a31d4 SHA-1: aa90c7f448296680dfe6385279f121a81b442aae SHA-256: 420a849717f01a1ea192f18e1256313add2212cdc5f119483dd1705ceedf0f48
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristic analysis revealed it functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics indicate.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://airfa.it/userfiles/file/fesaxejemite.pdf In PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/ad2354d7203331e489e0419001d2867d/66137709978.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/7864738933.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/2991448843.pdfIn PDF document text
    • https://bbox.ru/images/shared/file/sulariwufowigekixataku.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/86805813892.pdfIn PDF document text
    • https://www.bbmnetlicitacoes.com.br/cms/ckfinder/upload/files/dinose.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a6fb8a6ed1---gekinati.pdfIn PDF document text
    • http://cascad-trans.ru/files/lafidepokezatobedefavit.pdfIn PDF document text
    • http://yuha.be/_files/file/84664090467.pdfIn PDF document text
    • http://shesob.com/file/files/25034591092.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/52791688777.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16130fc2c98984---reziveva.pdfIn PDF document text
    • http://gestioniarmatoriali.it/xamokop.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614120afb77b2---jikixukesas.pdfIn PDF document text
    • https://parfumzone.ro/files/file/muxolin.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/44970954263.pdfIn PDF document text
    • https://khyatiinfotech.biz/ckfinder/userfiles/files/rosuz.pdfIn PDF document text
    • http://plenaseguroseprevidencia.com/fotosempresa/files/82672012974.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/78544233052.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/22761779067.pdfIn PDF document text
    • http://palmdale.thepokeluau.com/uploads/files/xapenojepew.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/2193320189.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/4f9cb9671ce4a532a6b0a5ae98637baf/42993587246.pdfIn PDF document text
    • http://rsti.biz/files/fck/file/16688238965.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=tales+of+the+otori+pdfPDF 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_off0000fa9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA9E 18468 bytes
SHA-256: 6ab3f82dbd186fddfe65654d265a5dcab7742f0b3707e2a424a24e953764554f
font_01_sfnt_off00012b4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B4A 10452 bytes
SHA-256: b7c429a72464a716fd9ff3c0b501ed81825d6b00dd22eb47df2b13335af1ea8c
font_02_sfnt_off00014325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14325 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1