Malicious PDF — malware analysis report

Static analysis result for SHA-256 d99d3cca8641febd…

MALICIOUS

PDF

69.7 KB Created: 2021-10-02 11:12:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 449d46dcb9138673f1527b1649920ae8 SHA-1: ea00757b153471c5ae6309360ddf6cdef72f3f5b SHA-256: d99d3cca8641febd5b4bd94573ff55b87026144532a139c079534b5e0e33363f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the presence of external URIs and the overall structure point towards the document acting as a lure to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://ketchas.ru/uplcv?utm_term=high+protein+count+in+blood PDF link annotation
    • https://goooinggroup.com/userfiles/files/20210922_174550.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/masalavegukar.pdfIn PDF document text
    • http://telecycling.org/files/file/wilif.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/87428415608.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/getevekepozokujirejitewe.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614b76ea18896---81707597176.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/ragizulepuvobefomif.pdfIn PDF document text
    • https://trinityautorepairs.com/uploads/files/nukemujarepasijir.pdfIn PDF document text
    • https://porfic.com/fotos/file/9373222761.pdfIn PDF document text
    • https://immo-cjeanpaul.lu/userfiles/files/pavuxujetedewumemajefi.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/7179139868.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/25851749605.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/19984288392.pdfIn PDF document text
    • http://ing-ka.com/user_img/file/84958770177.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/lakuxumigekeruwi.pdfIn PDF document text
    • https://francemonde.news/UserFiles/file/mowavunonigotuw.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/10291155965.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/jiroranibozegagos.pdfIn PDF document text
    • https://mcsfood.com/images/file/91348383412.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/pilajifopin.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/17267589835.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/84781037894.pdfIn PDF document text
    • http://nhadeptannguyen.com/uploads/files/godavizogovoxupur.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_off0000af3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF3F 16620 bytes
SHA-256: 0955e08815e4e16ae38a141cdeb8e40678b237d2e8c65f26a6436d38597f8e02
font_01_sfnt_off0000d984.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD984 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f19b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19B 10692 bytes
SHA-256: c13698b889c95259db4204ff472f73da24d1915658d1c0e46c8d74fd545cfbc0