Malicious PDF — malware analysis report

Static analysis result for SHA-256 b436d0766ae64218…

MALICIOUS

PDF

69.7 KB Created: 2021-09-08 23:53:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7eee69659ad9784914ff0c7894b705d8 SHA-1: 150d6a3da5c5fb294c102776765ff70489f49a8c SHA-256: b436d0766ae642187e8fd0e6894060c2ff00a5b0691adae9cd82945c7fafbfb4
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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 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://huntic.ru/uplcv?utm_term=chom+chom+fruit+in+english PDF link annotation
    • https://aydin-elektrik.com/resimler/files/99306474460.pdfIn PDF document text
    • https://renault-service.com/userfiles/duranuxodewumu.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16130ef525b7c1---51776489205.pdfIn PDF document text
    • https://manenshop.com/upload/files/xoxab.pdfIn PDF document text
    • http://bularz-auto.pl/images/userfiles/file/22563756834.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/jowivovisaboduj.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/lovijajuseruf.pdfIn PDF document text
    • http://dr-onesrl.com/userfiles/files/91786904456.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/56313329111.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/vimedilupufuzo.pdfIn PDF document text
    • https://krossi.ru/images/content/files/bajusepifagiva.pdfIn PDF document text
    • http://ksiclubcom.ksiclub.org/svnprojects/DHD/Source/images/files/xabof.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/1996406824.pdfIn PDF document text
    • https://haciendaloscipreses.cl/upload/file/22600592650.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/gubumukom.pdfIn PDF document text
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/12280116560.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/38810826363.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/mapatal.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138e466a4d31---61866183291.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/50088866570.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/61777654786.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/rudebitajekuzimewoxirezu.pdfIn PDF document text
    • http://penzion-u-zamku.cz/files/file/gezarofemuxiwifuguzer.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/diwojizorifomal.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_off0000b135.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB135 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC947 15944 bytes
SHA-256: b3e930029d5bc40fcea60cc5d96cfab13e25b36c45f1e51ecd6a6b02e0f69df6
font_02_sfnt_off0000f118.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF118 10752 bytes
SHA-256: b5e272f361c878f05b5a09307691c2fc1d02cad4e28bbc3564f223e346036647