Malicious PDF — malware analysis report

Static analysis result for SHA-256 215556e698d99834…

MALICIOUS

PDF

71.4 KB Created: 2021-10-11 05:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a81a581de2389a5fb03e73f7e4d2d2d SHA-1: a3c4944359c5d1d08688434378aa5ecd47ebc34f SHA-256: 215556e698d99834d89d70b3e27f734eac650dd067574ce8deb3788b6d43fe2e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many of which point to PDF files hosted on various websites. Heuristics indicate this is a link farm on disposable hosting, and ClamAV detected it as Pdf.Phishing.Trojan. The ML classifier also flagged the PDF as malicious with high confidence. The primary attack pattern appears to be distributing malicious content or performing SEO manipulation through a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://durimawar.com/contents/files/sikuvo.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16140f8323a21a---80217233288.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161347a805cd64---muxabimuw.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/cbe2e81e5b758e3162c5f511d897a3fb/61984659845.pdf
    • https://windscrm.net/files/file/60514457141.pdf
    • https://csp-pub.com/stockages/files/53436137080.pdf
    • http://cpgny.com/userfiles/files/dazel.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/7eca191994da7676197f465d37af84a2/5592520952.pdf
    • https://praktijk-fix.nl/userfiles/image/file/vosozaxuzamufijize.pdf
    • https://minhkygroup.com/luutru/files/lixesepapa.pdf
    • http://diagnosticaedilizia.com/userfiles/files/50668302938.pdf
    • http://vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/1713182473.pdf
    • http://cantinachitarra.it/userfiles/file/9018922034.pdf
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/52825966246.pdf
    • https://angkalaris.com/contents/files/panigikopaje.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1614c477e06a79---41642929500.pdf
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/kotonesogepepusa.pdf
    • http://biurod9.pl/public/userfiles/file/44392481317.pdf
    • http://jingyilin.org/uploads/file/poravawewivejimi.pdf
    • http://www.pes.edu.mn/ckfinder/userfiles/files/nuzonorizatamujijawe.pdf
    • http://dc-07b6a75bc4d0.breakthrough-physical-therapy.com/userfiles/files/gesimitefajun.pdf
    • http://testplanet.nl/uploads/files/lepowixesavoliretow.pdf
    • http://elateridae.com/images/FCKeditor/file/bilakurupibavirofiniwiba.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=externalities+are+defined+as
    • 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_off0000b842.bin
b5a4e4d9dbae5a2254bec16b7235acaf86c631c92299e3b9e7db59fedd4170a8
pdf-font-stream PDF embedded font (sfnt) at offset 0xB842 15764 bytes
font_01_sfnt_off0000e07f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE07F 16792 bytes
font_02_sfnt_off0000f896.bin
49bd23de2e97a76c4d187f830bb47a196c22c12967d0180f1a6ac049673cfe65
pdf-font-stream PDF embedded font (sfnt) at offset 0xF896 10312 bytes