Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad3656443053ef5a…

MALICIOUS

PDF

87.7 KB Created: 2021-09-16 19:53:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4403a17c015b9d4480b15592818f59bc SHA-1: 787b1f02bf455b735f93aeafc76ad1115817a97c SHA-256: ad3656443053ef5ad67b907b2852960c7218283e54b39930ed895c0c2c7c6779
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of an advance-fee scam. It contains numerous links to external PDF files, many hosted on compromised or disposable domains, suggesting a link farm designed to distribute malicious content. The presence of callback lures indicates a phishing or tech-support scam pretext. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit users through deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Advance-fee lottery/parcel scam lure high SE_ADVANCE_FEE_SCAM_LURE
    Document contains lottery/beneficiary or prize language together with large-value draft/funds wording and parcel/courier delivery requirements. This is a classic advance-fee fraud document shape.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://sampoernastrategic.com/uploads/image/files/vaxugobukagorasisaji.pdf
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/76386493305.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3aae4731e---jowen.pdf
    • https://gjbuyerbroker.com/userfiles/file/jufodufanumupubim.pdf
    • http://tatnhapkhau.com/ckfinder/userfiles/files/kikoduduzuvugapazexema.pdf
    • http://clinical-pain.com/pds/userfiles/files/2396583745.pdf
    • http://arniuniversity.in/ci/userfiles/files/vevak.pdf
    • http://drthchowdary.net/userfiles/file/67600721562.pdf
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/74410397447.pdf
    • https://zapret-rf.org/web/img/podborky/files/46688883203.pdf
    • https://juniorclublivorno.com/sitonews/images_upload/files/82881947008.pdf
    • http://bobas24.pl/Upload/file/52875893897.pdf
    • http://indyskischool.com/ckfinder/userfiles/files/gumapigalalewuxe.pdf
    • https://habibitoursegypt.com/ckfinder/userfiles/files/50045303748.pdf
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/12975975689.pdf
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/96859747457.pdf
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/91541574284.pdf
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3ce34436a---monurafugazerovixisasob.pdf
    • http://pieseclimaauto.com/files/file/najepifomidosegopekubugij.pdf
    • http://rigdrilling.org/userfiles/file/59917529830.pdf
    • http://narnivet.com/userfiles/files/92835552333.pdf
    • https://calendarsunrooms.com/userfiles/files/zakujegotoropitora.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613b71ab2dca9---rizisobo.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/7ad07079178417724dddc3af77bd4175/feferunaputagu.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/92640591056.pdf
    • http://gayaarchi.com/userfiles/file/20210906190524.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=best+multiplayer+games+for+pc+2021
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eec9.bin
f8965ccc2c611384a7bd44986a39398e05d3b179848fa9e2826bdd01730d9cf9
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEC9 18096 bytes
font_01_sfnt_off00011d94.bin
b77b3d349761a1f905cb21c058965e5af4316087e08c4c410c91ed864a6431de
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D94 11280 bytes
font_02_sfnt_off0001383e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1383E 16792 bytes