Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d711088c83bba5b…

MALICIOUS

PDF

79.8 KB Created: 2021-06-28 19:58:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 248ed32bce99d8ae190e1fab3d4c73af SHA-1: 4893198ececc0231519c0f3d2325e839bf01ee03 SHA-256: 8d711088c83bba5b085572bfbd8ec83530252841672f0df6b08a6b01fd641af2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, forming a link farm. This suggests the document's primary purpose is to lure users into clicking these links, likely leading to phishing pages or further malware downloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://huntic.ru/uplcv?utm_term=multiplication+worksheets+5+times+tables
    • http://e-hematologica.com/users//file/ligimuzisasis.pdf
    • http://yao-cheng.com/uploadfiles/20210620032545.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c544e0e5cf3---rokekivan.pdf
    • https://ksboutlet.com/file/files/25395888681.pdf
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/xovuxetofosabaded.pdf
    • https://idea-web.ro/app/webroot/files/userfiles/files/xidubefuvadamivewarem.pdf
    • https://jodhpurtravels.com/nbloom/fckuploads/file/97696801453.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/06133a95dae4b6dba18ce0ad96b7b44e/62867448633.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/3k04uig9n7rvo2jkodrdjcr796/68241221077.pdf
    • http://taxicityplus.ru/userfiles/file/wivez.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8cfb9f32a8---nisivas.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cebd245bb6---kadekotuwezizogaxuvijawux.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/5555a4c5b28c2376b7e55379c7a6b3c6/30821836481.pdf
    • http://temple.mo/userfiles/file/32264168680.pdf
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/abv64isa90t0rlsjjtdckt5fpa/desobuzenenabom.pdf
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1607056cb00daf---82699195423.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160964f733c37d---57967425416.pdf
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608109f880b9d---86755345696.pdf
    • https://agrilaui.com/userfiles/file/disibegadibazowuro.pdf
    • http://amoy-art.com/Upload/file/fageluwivilolutopiwilema.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/vksavjlkp6nl9tncik79tb3838/jopolanurolu.pdf
    • https://sailstudy.in/ckfinder/userfiles/files/vitutijela.pdf
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/0dd4aff32987e0330564843306c87c47/wilawugikimapovenunomizan.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bffccfdaa25---71585535173.pdf
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b68088013cc---vabovavaxetukalopoxebij.pdf
    • 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_off0000d407.bin
8d5a5f1e9e922fb685851f6f082ef0dc20a80235a083f1f1d7759d7b7a3d0805
pdf-font-stream PDF embedded font (sfnt) at offset 0xD407 16832 bytes
font_01_sfnt_off0000ffd3.bin
36eaf666fa2f8ca43e5f0611884f7f3f5f3a714c5c3f5ce5ec7f51e78973d4be
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD3 11184 bytes
font_02_sfnt_off000119bc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119BC 16792 bytes