Malicious PDF — malware analysis report

Static analysis result for SHA-256 c137f63cb7c3c2e7…

MALICIOUS

PDF

73.1 KB Created: 2021-07-03 02:08:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 234da92f3f85254bb9c596d2ce680edb SHA-1: bfd372840082dc2243ce100e14de3192024041fc SHA-256: c137f63cb7c3c2e7ed12748dac8d1e5f2f3d5b8c00af991541d5a156b8c3c53c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. These links likely serve as lures to download further malicious content or phish for user credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://przychodnia-felinskiego.pl/uploads/editor/file/fanukeliv.pdf In PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/82447a35c30017a21675150d8353d013/xadulumoberuk.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/e7al3mjvpmhjai7k1d1hkonigf/midalukurodapa.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/bejabufudizejos.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a00240d66a5---6517393205.pdfIn PDF document text
    • https://annjulieskarpmo.com/userfiles/file/10446213589.pdfIn PDF document text
    • https://solener.info/ckfinder/userfiles/files/93367463790.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/5266651191.pdfIn PDF document text
    • http://aimic.com/userfiles/file/lewipobemajuruwomuseleje.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/seronijuji.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/37554966773.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a995392c5---dezumerarorijelebevetowi.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/118e1629066dd6d85dc1754c022358a6/28751772095.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/5738c73c2db3dab20f8453861942001f/3353347316.pdfIn PDF document text
    • https://tasleemdubai.com/userfiles/files/gevubitegezasifivazebakar.pdfIn PDF document text
    • https://clove7.com/userfiles/file/setatijunojeposux.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/ladanaxekuximu.pdfIn PDF document text
    • http://hydrem.ru/images/file/67537175730.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/e0ff6bf45a785eecdcb24d38ab322848/72749981400.pdfIn PDF document text
    • http://budohurtsa.pl/userfiles/file/sedolo.pdfIn PDF document text
    • http://fygl.net/uploads/file/092230441012.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/bewijugub.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079fe931d2f9---51516542463.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0479636482---bajig.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=tie+fighter+video+gamePDF 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_off0000bd9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD9A 16112 bytes
SHA-256: 79c79c29b6afea47cb9d5f071e30ba82007225e21c5ccad0060428595d5ead8d
font_01_sfnt_off0000e796.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE796 10512 bytes
SHA-256: f5be2e451237086c74e4e184c313e9c29e5670d3e9c44488d28d50640ece50d1
font_02_sfnt_off0000ff5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF5B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1