Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9279db05045f3bf…

MALICIOUS

PDF

78.3 KB Created: 2021-09-24 00:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 20446783716b0012b039791301501e3d SHA-1: 14386d7869cf0989918a4d2b14652e572a148b3a SHA-256: b9279db05045f3bffc26b8540cb349cd26f5fd4788327e40e537ca8f7711f144
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to potentially compromised websites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this file as malicious, suggesting it is used for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the presence of multiple suspicious links is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://alasclub.gr/neuro/ckfinder/userfiles/files/20839106555.pdf In PDF document text
    • http://crystaltrade.hu/data/file/94936123360.pdfIn PDF document text
    • http://lovesushiscv.com/uploads/files/mazezikasatovo.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/fesojazobiwulasi.pdfIn PDF document text
    • http://rqconsultores.com/userfiles/file/bitulitutijatubof.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/gedijebenudekixaja.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/da5807cb8a821108bec27908e2d4b446/kozafimezotaxa.pdfIn PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/35977908979.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jonopujamuso.pdfIn PDF document text
    • https://sbmhavacilik.com/userfiles/file/17721700019.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/beguzokaniri.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/09ef7158b8789d3801c2395160eee3ad/jujujusoramumavaxa.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/juzeluzuvo.pdfIn PDF document text
    • http://digifast.cz/userfiles/72203824903.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427e396fe32---davuvejepenareb.pdfIn PDF document text
    • http://arisutour.com/ckupload/files/vofarowatigaju.pdfIn PDF document text
    • http://sushi-belovo.ru/files/10544649354.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/5b1ac9f7ec3abb6864c2f4b4ace5ac54/77940767059.pdfIn PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/85721757245.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7aadcf7c5---51202341130.pdfIn PDF document text
    • http://darstin.com/userfiles/files/21836773898.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/15519720168.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/kiloxunumalegije.pdfIn PDF document text
    • https://weboonline.com/ckfinder/userfiles/files/dumiferaf.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/jipaboxed.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=launcher+settings+apkPDF link annotation
    • 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_off0000cb96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB96 18460 bytes
SHA-256: dd7abd31f13fc3410217124d887e11faac384f681ff5ba747b1ab05ed3ac1ada
font_01_sfnt_off0000fb4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11362 10636 bytes
SHA-256: 64173d2564160828d333d73c7c888d1250382666fff37df01b1d58618ea14dc0