Malicious PDF — malware analysis report

Static analysis result for SHA-256 273990a52dca238b…

MALICIOUS

PDF

74.1 KB Created: 2021-09-06 04:26:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9ea13a92cb1384bb946c7b39976d375b SHA-1: c132a11d3938c9f9e1adc6008c76f12812f83070 SHA-256: 273990a52dca238beba582f1880e9bdc5dc836cd0abd9b36258eb9f5a3794a9c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://wastran.ru/uplcv?utm_term=body+organ+systems+worksheets+for+grade+3 PDF link annotation
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609982a825302---2897024730.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/danewu.pdfIn PDF document text
    • http://mikailang.com/userfiles/file/20210822101457_380130497.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/cb2d929f31bfdf3ec6264cd16e3462ff/kesopuxabexiwajujufupu.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a284b565342---95776923205.pdfIn PDF document text
    • http://natproperty.com/userfiles/files/nibekevosadulus.pdfIn PDF document text
    • https://anukulagrotech.com/userfiles/file/mipujamobamenirokowosixam.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/jikemine.pdfIn PDF document text
    • http://safarang.com/basefile/files/34544301635.pdfIn PDF document text
    • http://aquinasnb68.com/clients/9/9b/9b9a52ed12f3b440fa02b6ce64642487/File/44967384442.pdfIn PDF document text
    • https://southafricapools.com/contents/files/45002527966.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/nafabutuxojuturazug.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/xunulefenodoratudomumo.pdfIn PDF document text
    • https://skillmapmagazine.com/ckfinder/userfiles/files/xiwuj.pdfIn PDF document text
    • https://eslms.com/userfiles/file/bevelibo.pdfIn PDF document text
    • http://klwas.org/userfiles/images/file/882910973.pdfIn PDF document text
    • http://jimsclub.net/new/board/img_tinfo/file/20210816121148.pdfIn PDF document text
    • https://ancoraeducacion.com/images/sajomoxudel.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/bilebuletezowijimadumef.pdfIn PDF document text
    • http://proxkimya.com/resimler/files/80069862023.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/amc9b1l95ggnf2aqtvj5sd8gue/61071789388.pdfIn PDF document text
    • https://global-product.org/CKEdit/upload/files/54820034002.pdfIn PDF document text
    • http://santabruna.cl/upload/file/60016332889.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/damuzudiridikiful.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/14344647037.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_off0000bc6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC6B 17612 bytes
SHA-256: 85a6d587d629556b1e7995d40a98d06d4f46a706fabfa8378af5233f98bf45e7
font_01_sfnt_off0000e8d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100EA 11180 bytes
SHA-256: e1b4d1664807bbf3507f8cca06336dc0f2f4a9810a15746855c950206af861d3