Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd502561c33ee8c3…

MALICIOUS

PDF

73.4 KB Created: 2021-10-12 14:55:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2203569e8bddb3f96f7f300bfc2de5ae SHA-1: 8df65812febc843dd59cdbe57e3ea734f7c796a3 SHA-256: fd502561c33ee8c3f8322f4bf243798b35d6ddd7b6ebac19efb9ae5d513ffad8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting it acts as a lure or redirector. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating a link farm on disposable hosting, a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://fini.hu/userfiles/file/luremekoxubenuwigone.pdf In PDF document text
    • http://korea-seals.com/ckfinder/userfiles/files/jerapazeroreromotadufuvu.pdfIn PDF document text
    • https://demideopool.ro/ckfinder/userfiles/files/43192896362.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/26212260749.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/23897139126.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/97781422003.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/34227091155.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/lajoliripibamewexur.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/20875550660.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/ed0b500c302c5922ae9f19cca509cb69/dulikemawi.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/rinelelijenuw.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/43564884577.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/39605291607.pdfIn PDF document text
    • https://alansglobalservices.com/ckfinder/userfiles/files/rujojevesizivadaju.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/17472910729.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/77233142932.pdfIn PDF document text
    • http://xn--9i1b14lzokxjcrti5um.com/upload/fckeditor/file/57748817773.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/95825592815.pdfIn PDF document text
    • http://bestbuyfromindia.com/userfiles/file/80654825487.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20210924_203552.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/99319133084.pdfIn PDF document text
    • https://getadoc.in/ckfinder/userfiles/files/vizifuxevozafuv.pdfIn PDF document text
    • http://toitureetfacade.fr/data/Files/9063114828.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/tetux.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/oscUj7J0Gjw/uplcv?utm_term=pan+fried+green+tomatoesPDF link annotation
    • https://b2cdemo.tickets.com/content/files/tijuvikiditoposi.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://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_off0000bd83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD83 10652 bytes
SHA-256: b95e159bb164c955f93fbbd7fca5c161227291268714bb20f98a9224d2977814
font_01_sfnt_off0000d5a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A6 18400 bytes
SHA-256: b98ffeb8dd66815884502c869ed9f5fc2e1d568e69c28648c6bb37032eaf1211
font_02_sfnt_off0001049c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1049C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1