Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8f6869ae85cfccd…

MALICIOUS

PDF

81.7 KB Created: 2021-09-16 04:31:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ed4a95a26f4c6aee8e382cbba74cf593 SHA-1: ed1e59355251bc6d7533bdcce63ffc55adac7d59 SHA-256: c8f6869ae85cfccd8ff3dc7d728c82a19dae70680c6b8d51a988a8cd5e4ca522
126 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with a high number of distinct external URIs, many hosted on disposable domains. This suggests the primary purpose is to redirect users to potentially malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://fitviewer.biz/files/file/28588773482.pdf In PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce62e05d0d---katudovagajelazuki.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/sakijidu.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/zebivedomazunabumeza.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/bekuzitozepasij.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/tolisali.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/81902565559.pdfIn PDF document text
    • https://photojet.bg/userfiles/file/51183943893.pdfIn PDF document text
    • http://f1-rennsimulatoren.de/userfiles/file/56359037457.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/vewogu.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/fisafiv.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/savotogaxax.pdfIn PDF document text
    • http://chemtron-vostok.ru/media/file/97850737156.pdfIn PDF document text
    • https://quangcaowebsitecomvn.xemlaco.com/uploads/files/15216712457.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/93536c71adf543baa9b71a837091d598/vaveluraxube.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/gitegiguxulepukitofas.pdfIn PDF document text
    • http://www.sec-ollivier-associes.fr/www/upload/file/45348854590.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/34135335034.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/65894152498.pdfIn PDF document text
    • http://tsraccountants.nl/mailing/images/photo/file/75089138737.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/44596998547.pdfIn PDF document text
    • https://hurghadalife.net/userfiles/files/bexezajitoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=eep+full+movie+online+english+subtitlesPDF 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_off0000dd12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD12 16812 bytes
SHA-256: 62e6a8b37e66685b6720e499179678b393ecec7bc53e3b1e52481f92971c6275
font_01_sfnt_off0001087b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087B 10832 bytes
SHA-256: fa603a6d966911a542282e7a83d66e783e33dd8df06bc32206cb3c1794137bad
font_02_sfnt_off00012111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12111 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1