Malicious PDF — malware analysis report

Static analysis result for SHA-256 67f9a7bd8c58c171…

MALICIOUS

PDF

86.8 KB Created: 2021-09-14 09:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 8bd9ba0ed141799dca48669b14050e13 SHA-1: 895082ad60a3ebf81129f2c6c54a1103fcfce8c9 SHA-256: 67f9a7bd8c58c171fb6ba7e80aa0633d30bd1ae1118a02be2d35bafc2872b223
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to domains associated with link farms and disposable hosting, indicating a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, pointing to URLs like https://ambulatorioveterinariosismondi.eu/file/76222501854.pdf and http://brava-ekb.ru/userfiles/file/vixowani.pdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://coretry.ru/uplcv?utm_term=get+free+instagram+followers+2021 PDF link annotation
    • http://brava-ekb.ru/userfiles/file/vixowani.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/67801842873.pdfIn PDF document text
    • https://signos.larrialdiak.es/files/galeria/files/losofoxolupex.pdfIn PDF document text
    • http://xahscw.com/userfiles/file/74367316284.pdfIn PDF document text
    • http://nc-israel.ru/upload/files/89015500324.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/83936909920.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/2942403611.pdfIn PDF document text
    • https://tssch.in/tssch/application/admin/uploads/file/dekunodavojafapesefavag.pdfIn PDF document text
    • https://ksuskalology.com/images/file/77474953453.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133d16e474be---xabizowapapugozuwokaroson.pdfIn PDF document text
    • http://hotelniagararimini.eu/userfiles/files/dakuf.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/84441668877.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/lixorikanan.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/76222501854.pdfIn PDF document text
    • https://signika.pl/Upload/file/95594400750.pdfIn PDF document text
    • http://architettobotteonpierpaolostudioabacus.it/userfiles/files/81437380546.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/v81hlvi05rursnej7hinloof9j/13789653211.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/12284683617.pdfIn PDF document text
    • https://btsmstlucia.com/atomicsteps/upload/userfiles/file/kebevuposofopu.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/45119444269.pdfIn PDF document text
    • http://synfarm.com/upload/files/81484303067.pdfIn PDF document text
    • http://tongrentangthai.com/UserFiles/file/8339189040.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/4278463671.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_off0000ec4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4B 10976 bytes
SHA-256: d668d45722838dc6bc6223ce44fc82f516a71a9a9511a5b695862930f41ec85c
font_01_sfnt_off000105ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105EE 18236 bytes
SHA-256: 5937dd95e533cd8e014ec034384ca3ca9a97658db1c21c2c7203a149d8c23ad9
font_02_sfnt_off0001350c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1350C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1