Malicious PDF — malware analysis report

Static analysis result for SHA-256 78169bc813682d72…

MALICIOUS

PDF

69.2 KB Created: 2021-09-13 19:46:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 05fe33387cc88f259d0c97f880d8794e SHA-1: f4a8fe359c26fd29827b50bcc9dfab2812a133b9 SHA-256: 78169bc813682d724b74617672c9a776b6afd0642876ed23a3c8a8441a5d1c76
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a link to an algorithmically-generated URL and being part of a link farm on disposable hosting. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it is designed to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://xn--oy2b9bv81anouola.com/upload/file/202109110011492119.pdf In PDF document text
    • http://canyonmeadows.org/userimages/zobozizatifanos.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/62525273091.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613e335536e00---94643290200.pdfIn PDF document text
    • https://greenways.at/userfiles/file/kevukipasediromu.pdfIn PDF document text
    • http://eaupureinternational.com/userfiles/file/44377385812.pdfIn PDF document text
    • https://eownauto.com/uploadpic/files/werukudakat.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/bawetepovov.pdfIn PDF document text
    • http://bonsite.nl/phpcmsys/file/gaxuvubukawezoxisopur.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/29955367538.pdfIn PDF document text
    • http://bimbrlata.cz/UserFiles/File/pabosatabow.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/58366972410.pdfIn PDF document text
    • http://world-green-hope.com/uploads/files/tekonomerok.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/laxugan.pdfIn PDF document text
    • http://ithalattagarantibelgesi.com/resimlerfiles/moxovenavom.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/76468193878.pdfIn PDF document text
    • https://nexapos.com/upload/files/23298977476.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/plsbhui892b44ffm7ae2on7761/goketezegoju.pdfIn PDF document text
    • https://ip-kamera-rendszer.nuttydog.hu/ckfinder/userfiles/files/57663505709.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/mebeworaxadejedo.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/54906265377.pdfIn PDF document text
    • https://magicdiscoradio.com/userfiles/file/sufogubejunida.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/jefimowi.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/dowegaxubamugu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=tanix+tx6s+firmwarePDF 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_off0000af87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF87 15664 bytes
SHA-256: 658d5a1c6957c504043bde3a77e790e1d32ee41b9018e3b79b5c9a68b3e42711
font_01_sfnt_off0000d76b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76B 10528 bytes
SHA-256: 69066c9c4e47f99a1337313e79693b7ccb6c127edb9e67e3c56cbd30351a17ba
font_02_sfnt_off0000ef8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1