Malicious PDF — malware analysis report

Static analysis result for SHA-256 1100cfbd3af469da…

MALICIOUS

PDF

88.7 KB Created: 2021-08-14 01:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 27bb0d49347d12c06e794342e1eefd3a SHA-1: 6a4d3903efdbdcd49b8753dec7b7e544e3634d19 SHA-256: 1100cfbd3af469daa076aeaa1a9712d05ffa147b2f7c1805c91fff20d81c6032
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, containing numerous URLs that point to compromised websites and disposable hosting, likely to redirect users to malicious content. The document body is heavily obfuscated and contains no readable text, suggesting its primary purpose is to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://archism.ru/uplcv?utm_term=funciones+trigonometricas+ejercicios+resueltos+rubi%C3%B1os PDF link annotation
    • http://findmecakes.com/userfiles/files/46799526719.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/90239162669.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/wigulegotenikefufut.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b43566b3c2f---48818516547.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/561734b82cfc4c3b4ce134ffb6c70a80/49457644064.pdfIn PDF document text
    • https://tenekedjieva.com/uploads/file/74791745955.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/a747a3af8c9206d38af433b7a18b4c21/nevaluwiseder.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/87609984464.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/83679431183.pdfIn PDF document text
    • http://ryouhurt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18658438406.pdfIn PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/vekige.pdfIn PDF document text
    • https://georeno.ca/userfiles/files/30424282610.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a391085eb73---faxobomuvominizuseliru.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/gotazokifedudexumi.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/c1e046798eb636fb96245ec9e1624a3d/26333393527.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/midebadofakarifu.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f21b461d19---jebuxipi.pdfIn PDF document text
    • https://fajndoktor.cz/images/file/files/3423788590.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a271be2d42d---karozapabujewinutiluxugip.pdfIn PDF document text
    • http://henri-ruch.ch/doc_pub/file/rejonetizemorujuj.pdfIn PDF document text
    • https://voyagerf.ru/wp-content/plugins/super-forms/uploads/php/files/b969c2191eb5e28965e44ddde29f01d5/49804083404.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/631u9dpjgol6qodm4amc0sp6ja/befexibuxitarevo.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/43742062092.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/77308800861.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_off0000f3f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F2 17216 bytes
SHA-256: fbcd46257870ebbbd21a432955213d7e399d3fd32b5b04d283b23544916757e8
font_01_sfnt_off00012003.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12003 11124 bytes
SHA-256: dd2bbdb649b26a185f8f0d499969ace3f2999f2fe4ad6b46245c102cf65fe6b4
font_02_sfnt_off000139b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1