Malicious PDF — malware analysis report

Static analysis result for SHA-256 13f925a1d7101ab1…

MALICIOUS

PDF

69.5 KB Created: 2021-09-23 06:01:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4336c9e4e051b30720aedf653c0be6b6 SHA-1: 4b9656d26d49248cc45bc8134ab7350532d0e01d SHA-256: 13f925a1d7101ab187b1797c666c3e2d99aa0a22a36cebd09a7cafef966682fd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a spearphishing attachment designed to lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://orel-trinity.ru/sites/default/files/file/votunokudobuxede.pdf In PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/161404d04d6d05---98562254233.pdfIn PDF document text
    • https://pmeds.us/userfiles/file/jokokilojure.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/77136640350.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/57090396335.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/likugepedugupulol.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/71016269567.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/wopozifekotesowerune.pdfIn PDF document text
    • https://perfumes.dropship-tracking.com/userfiles/files/pitupajidolusu.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/33849929273.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/gugitewavilatetu.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/femovabawuzu.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/kogosibedo.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-9-19/20210919040009762164.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/53487698054.pdfIn PDF document text
    • http://themadthinker.com/temp/vinney/HTML/userfiles/file/sanalisepazaxamalugot.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16148d4af925c2---kasosuzanixosizexetug.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/22586023191.pdfIn PDF document text
    • http://lakesnwoodskerala.com/uploads/file/28753093867.pdfIn PDF document text
    • http://guss-ex.de/uploads/fck/file/86173364677.pdfIn PDF document text
    • https://12shio3.com/contents/files/70794450441.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/rixipejow.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/pokukarosirugizafazuda.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/sozidenovil.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/86087369093.pdfIn PDF document text
    • http://1000projects.ru/upload_picture/file/72796114661.pdfIn PDF document text
    • http://sladkiy-ostrov.ru/userfiles/files/86859948765.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=tom+tom+mod+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_off0000b30a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30A 9968 bytes
SHA-256: e6a7db88a09a9ff3e322e71255257a5f45c5edd2fbfcaf00eb0cf64245d09bbc
font_01_sfnt_off0000c91d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC91D 15548 bytes
SHA-256: 64ce8b0a9ef0ab6e3daa4ca3e7fc362a97b3be9b0d3ada150818965f7dfee1a8
font_02_sfnt_off0000f086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF086 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1