Malicious PDF — malware analysis report

Static analysis result for SHA-256 77fd4b8841cd0671…

MALICIOUS

PDF

74.6 KB Created: 2021-08-29 10:25:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9b72425b1596d5464aeace2dd4d7c839 SHA-1: 52807decfe0a967f88557f891b8f7e24c5237991 SHA-256: 77fd4b8841cd0671586e056c78e5d7105faa729ff2bc5dc9c67d950ce0989b02
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to various domains, some of which are hosted on compromised CMS uploads. The presence of numerous URLs suggests an attempt to obscure the ultimate destination and potentially distribute phishing or malware payloads. No scripts were extracted from this sample, but the overall structure points to a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://wastran.ru/uplcv?utm_term=best+screenplays+of+all+time PDF link annotation
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/5nhomv5c5mglfjkpecnir4dumr/sopatate.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160add72b2d838---48170324467.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608134c3a8e19---20930447727.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/famog.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/362e017d9b3667f5523329b2ba416912/45584046748.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/87778964090.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/2169857806.pdfIn PDF document text
    • http://advicetao.eu/pictures/file/jotubefewujefew.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/76852487797.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd0b9b3dbb---84929534672.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/6482533443.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/s740f2ucihk3l4pg8ihb3bngga/vuvelowidu.pdfIn PDF document text
    • http://qqsbg.net/uploads/file/581541936.pdfIn PDF document text
    • http://shahnawazonline.com/uploads/files/21389195218.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/75549595534.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a36ed937bc2---juxok.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/4431012032.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/3ea32fa78265d07a17e95a69f176205d/vowijopu.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/4327405202.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f8316d07f---lipamexadojomepivajaju.pdfIn PDF document text
    • https://ambalatender.com/upload/files/nosenutafupej.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/19813312109.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/xetetomawu.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/vsd3to4ur5lpfdhvlqfo57mpo6/baperob.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_off0000c02f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC02F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d846.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD846 10808 bytes
SHA-256: 5032d90b283f88a27844fd9bfc7aca7a05763f6b0647274e685c00b88d52087c
font_02_sfnt_off0000f134.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF134 15964 bytes
SHA-256: f06b20a9c95c3c86e0f01d6ddcc818950c73363eb538d7cf4a81b5dbe5f44ac9