Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f3b84c3b2db539d…

MALICIOUS

PDF

81.0 KB Created: 2021-09-09 10:10:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 93178c4c8799bbf9028988a44b2080ba SHA-1: 4318939ae455e5743467ab8e093d87e58351e3a0 SHA-256: 9f3b84c3b2db539df30fb0c706c411d8a4c8dcae63e96679730aa6d360dd61a7
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with several pointing to domains that appear to be part of a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack by directing users to potentially harmful URLs.

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://synerhu.ru/uplcv?utm_term=how+to+change+my+font+on+my+phone PDF link annotation
    • http://qunjl.com/userfiles/files/61066075793.pdfIn PDF document text
    • http://jfhcoaching.com/userfiles/files/91748754281.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/zepoxinavewijomipew.pdfIn PDF document text
    • http://hotstamping.pl/files/file/zajefidafokipuwi.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/58425615976.pdfIn PDF document text
    • http://meuble-tunisie.com/userfiles/file/rugape.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/tedalakoxarekupiwin.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/96416757950.pdfIn PDF document text
    • http://ore-processing.ru/d/files/33553030451.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1612ece51543be---41086353321.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/70379747796.pdfIn PDF document text
    • https://sgicorp.com/userfiles/files/85948628318.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/92911098340.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/pogumedu.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/74573843587.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/48926528220.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/bibepeb.pdfIn PDF document text
    • http://landroverbh.com/ckfinder/userfiles/files/famitufuxukanagujatunugi.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/72946727264.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/46643172922.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/tavamezejupopakefizoxif.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/91701069193.pdfIn PDF document text
    • http://gorod-r.com/userfiles/file/70799670699.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/vafamorilawimitawa.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/jifozerefuxubi.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_off0000d593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD593 10712 bytes
SHA-256: 4bec92529ae0bd1a46de3062686b15f7f51a0e5501d187a2819cce90a12a843a
font_01_sfnt_off0000ee08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE08 18428 bytes
SHA-256: b09812570e0e172c20325c03ee4d24adab4d57d33bdbe150e72979e8a7df347a
font_02_sfnt_off00011e34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1