Malicious PDF — malware analysis report

Static analysis result for SHA-256 33273738f33f5af9…

MALICIOUS

PDF

80.9 KB Created: 2021-09-12 17:55:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 45afba34271a0a9b68fa0be010410b73 SHA-1: 2acd483685ace7794f26701a82a2d64869cc6f3c SHA-256: 33273738f33f5af96ee85d59066a9a675bc69eb8455aa9ed8ef9ea6f3a4217fd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious redirection tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://tdvvietnam.vn/webroot/img/files/nafixusepon.pdf In PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/9831921134.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/3f03aab23677e65ba357f08265c2ee1e/luxedekegerupebobeli.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/sawulet.pdfIn PDF document text
    • http://giaexploring.it/userfiles/files/dexowovebemu.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/93815363851.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/99295544976.pdfIn PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/62140796348.pdfIn PDF document text
    • http://chukguwang.com/files/fckeditor/file/wekezisizojakuvotabafir.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/goxowijoduvu.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/lawapugasi.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/16177229258.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/togvs6g7lt1qco8l6ub71sfsi2/34002780565.pdfIn PDF document text
    • http://sipsak.nl/userfiles/file/53200630458.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161331944882d0---zezonupatuwapasepuwagis.pdfIn PDF document text
    • http://netmode.net/app/webroot/uploads/files/samazepen.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/83040933281.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161335ed2700b4---xepimilinuwawetikovetodi.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/161396c4b91f95---vimir.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/bagowiwasalewikinebuvat.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/51098507393.pdfIn PDF document text
    • http://inwallendorf.de/userfiles/file/15268917176.pdfIn PDF document text
    • http://dichvumucin.com/upload/ckupload/files/68225698980.pdfIn PDF document text
    • https://luiginoiobbi.com/userfiles/file/47904900592.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=i+am+the+night+episode+1+watch+online+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_off0000d2e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E6 18924 bytes
SHA-256: 58b2fe7a5c3107c07271d8c99457d5bb17effd9b1bbd3c05fa5eb3cd7d436baa
font_01_sfnt_off00010378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10378 11156 bytes
SHA-256: 2d0ff5ef821cc2d5d6ebdc0c3e1093db920bda1c321a1dc8c68fd705c2bd8ebf
font_02_sfnt_off00011d40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1