Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91d3923917ab79e…

MALICIOUS

PDF

74.1 KB Created: 2021-09-09 07:58:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 052ac43081affacada82f64b1ac5a28c SHA-1: e096862199064a1f97ea47e45cd1fb34f2f16c19 SHA-256: a91d3923917ab79ec2549dbb82b9be80ef503dae1ffea75d6541beabaccde7fe
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Numerous embedded URLs point to potentially malicious domains, suggesting a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of malicious intent, likely related to spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/xasabotubepizuvudonu.pdf In PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/koralureser.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/58272352585.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/82433591646.pdfIn PDF document text
    • https://fundacjaartfreeart.pl/userfiles/file/84505927939.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/14753657293.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/luditakuli.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/08df27f4e5b1598455bc3f1f5c80137b/92948899110.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/ratewijomuful.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/53758710850.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/pumeruwa.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/58208890556.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/52946805652.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/69972087352.pdfIn PDF document text
    • http://falcon.dk/sites/default/files/webfm/lifinebopisosep.pdfIn PDF document text
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/25435667730.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/nizunoridaforarilozokodum.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/bodudodowotokosopekunes.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/2f263f7def76cbf3178346137ba2e2b4/wujinijixunujixijefu.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/bemebivuvapasoxejuz.pdfIn PDF document text
    • http://flapboxes.custompackageboxes.com/userfiles/files/34024619616.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/67577283788.pdfIn PDF document text
    • http://suamanhinhlcd.net/userfiles/file/sevimidaxes.pdfIn PDF document text
    • https://piti.leaddeehub.com/userfiles/files/pakexumewojeteraxasumuw.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/xolafunakezekupijukedozo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=13.500+v+bucks+freePDF 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_off0000beb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEB2 17148 bytes
SHA-256: a4a5e1fdf7922226bffd4f0d964291ec80bc31d9102242aa24ba9aff1a7dbac9
font_01_sfnt_off0000eac3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC3 10556 bytes
SHA-256: 9e0f0c4923e719c19d86a65958684f6bea0bc56aa651d089ed67a8ec31d4f6d8
font_02_sfnt_off0001031a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1031A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1