Malicious PDF — malware analysis report

Static analysis result for SHA-256 f733eb2d66440a03…

MALICIOUS

PDF

84.5 KB Created: 2021-09-06 16:07:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6e9eb32a155100e1d2136e3ff0e607a0 SHA-1: 7163f89f411e27901192ecc2611949c64ae625ca SHA-256: f733eb2d66440a0340d383267de631f0a327d14dce67e62d57c471bc16e83bbe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that exhibits characteristics of a link farm, with numerous URLs pointing to disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it's designed to lure users into clicking malicious links, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nhachoxebus.com/upload/fck/file/zewukifavijexivupibixebun.pdf In PDF document text
    • https://vieclamxaydung24h.com/upload/files/vufareb.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/34400037497.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/51106793332.pdfIn PDF document text
    • http://ewtch.com/upload/files/zodovamivepuf.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/339210b432f7e6c6ae83b840eb9cdf92/82958750572.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/xujiziriteriji.pdfIn PDF document text
    • http://hulstcustoms.ru/uploads/files/62395970161.pdfIn PDF document text
    • http://www.vikingmaterials.com/img/jubulurikenavot.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/zonovutiluranutuzutopa.pdfIn PDF document text
    • https://mkart.it/uploads/file/15296220302.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/zevakalimori.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/saninuruwane.pdfIn PDF document text
    • http://macap.nl/app/webroot/files/userfiles/files/71789070942.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a161d7a101---xemepumiduti.pdfIn PDF document text
    • http://vikohasanfiber.com/upload/files/posubapati.pdfIn PDF document text
    • http://edumedcare.pl/upload/files/81402707073.pdfIn PDF document text
    • http://chhsmahs.com/clients/8/83/83f479e57a8bbaec88b4a04d821ef24e/File/12095216635.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/abcb63a342674caa4dd33a9fb31b1f87/50620379972.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/vuvutibuxul.pdfIn PDF document text
    • http://canvangdientu.com/images/file/menebewurum.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/ce37cbb04e6031fe3a4d5818cc17d53b/66987294666.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/kozovuso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=libros+de+soteriolog%C3%ADa+pdfPDF 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_off0000e096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE096 19704 bytes
SHA-256: bbecbc948d5ddee6a44d2a2e9752ae3c7d7c99b421403186496b4edfaf73937e
font_01_sfnt_off00011284.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11284 10728 bytes
SHA-256: 0cf1db3aedd0f640a9abfa878896d3388470d3046797595a52d6117e3719e7d5
font_02_sfnt_off00012ad6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AD6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1