Malicious PDF — malware analysis report

Static analysis result for SHA-256 40e4cc9f3287f09a…

MALICIOUS

PDF

71.3 KB Created: 2021-09-14 09:07:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 05ab73049b6ef803770d12b6302dbcd3 SHA-1: 62b49b2123ce9d1b8820da183113f29dddfe97df SHA-256: 40e4cc9f3287f09a624a568baedf3e30acd5dae15aadab8b82aba52de121a9ec
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the use of link farms for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://medvor.ru/uplcv?utm_term=bubble+blaster+game+online PDF link annotation
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614012da4cfca---jemiwitotoge.pdfIn PDF document text
    • http://osingenieria.com/images/admin/file/4114454880.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/86dd3eaf0bf4ede3f1c746b68fc45584/lakawifuworezisoka.pdfIn PDF document text
    • https://yunglin.com/uploadpic/files/83888905054.pdfIn PDF document text
    • https://equantumconsulting.com/files/files/ligirejesojajefo.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132ec1a9df3f---fokawimika.pdfIn PDF document text
    • https://cemb.ca/upload/editor/file/dorabomigi.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/seduselezexatamewonoribeg.pdfIn PDF document text
    • http://industra.sk/userfiles/file/22713685205.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/jojusekibuzatixafaf.pdfIn PDF document text
    • http://czyxchem.com/upload/files/4207555250.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/39900532631.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/zukapezovivebo.pdfIn PDF document text
    • http://wpchkg.com/upload/image/file/napulatimatosozajer.pdfIn PDF document text
    • http://campingwithconvenience.com/files/files/18976837276.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/32080912057.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/nejixanipidomef.pdfIn PDF document text
    • https://mmeasar.com/mmeasarfiles/file/rawezigidikojudesaf.pdfIn PDF document text
    • https://kaskad-74.ru/images/uploads/walezuwinusufozew.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/lilad.pdfIn PDF document text
    • https://www.thic.net/plugin/ce1/ckfinder/userfiles/files/najijobobojilijejokeb.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/99646628043.pdfIn PDF document text
    • http://protok.pro/upload/files/xamokefepot.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1630601526.pdfIn 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://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_off0000b8c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8C1 14964 bytes
SHA-256: eb312771cc88e096834ffa2124ddfc88ce7d3fab84e154dbd2b7503162de9685
font_01_sfnt_off0000de6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF684 10744 bytes
SHA-256: db16b55ec0e0ae7ea94002d78e1123a891c0cb7db0575dddc27dd34a800d7d84