Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c8cd73b3bf0b7fd…

MALICIOUS

PDF

85.5 KB Created: 2021-09-18 06:56:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 841be405a79ac537a9817df924608753 SHA-1: 14f7497593cc7b016acd8402656cc5907d60a833 SHA-256: 8c8cd73b3bf0b7fdc08be47dd078c6ee7cd20739dde6e18c9004fdbbdcff5849
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://trevorhannant.com/94632423879.pdf In PDF document text
    • http://turchifiltri.com/userfiles/files/22871975520.pdfIn PDF document text
    • http://louisamerino.com/userfiles/file/81743857629.pdfIn PDF document text
    • http://eapver.com/upload/ckimg/files/202109170015035054.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/tegiwixu.pdfIn PDF document text
    • https://draw.pt/home/drawpt/images-editor/file/mepejogimudinod.pdfIn PDF document text
    • https://designclarf.it/file/nudamukereniwimudale.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/42114978766.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/72128922823.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/39220137418.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/98889951271.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-13/20210913081710410720.pdfIn PDF document text
    • http://urbanelect.com/userfiles/file/jixaxuvosiriwulejuzefari.pdfIn PDF document text
    • https://rybczewice.pl/userfiles/file/44165808721.pdfIn PDF document text
    • http://urs-certification.com/gais/image/file/72760227090.pdfIn PDF document text
    • https://pastijptoto.com/contents/files/tubuzok.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/28eeca30c59315f440c2e18bf6155e52/73179701867.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/davinedevogojaxajozo.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16142e264c0301---92670361541.pdfIn PDF document text
    • http://brno-skoleni.cz/ckfinder/userfiles/files/88167362648.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///monug.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/13232438971.pdfIn PDF document text
    • https://creteotels.gr/FCKeditor/userimages/file/7302056992.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/56975229915.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109170551264491.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/86100310747.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=tera+warrior+buildPDF 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_off0000ea3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3A 18268 bytes
SHA-256: 1ec9e084800da048d021ad469102c76841d986f43be69de7e26f774b3c0eb2fb
font_01_sfnt_off000119b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131CA 10160 bytes
SHA-256: 5e9cdf4edcbfd615f9b02d1cec6ae496cbdf4f2fb188131d3647782f4927bb13