Malicious PDF — malware analysis report

Static analysis result for SHA-256 a96aebefe20fe918…

MALICIOUS

PDF

102.6 KB Created: 2021-10-05 01:54:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: e1de5b73530c9313ac65a81487175414 SHA-1: cb99326f2c3a0ad20fc9d48a4628faeec5e12759 SHA-256: a96aebefe20fe9184c57723f3dcd894dd0123ee4aa8f397cef9f5dd6b88cc1e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs pointing to compromised websites, many of which host other PDF files. This behavior is indicative of a link farm designed to redirect users to malicious content, likely for phishing or further malware delivery. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://smidgel.ru/uplcv?utm_term=possible+zeros+of+a+polynomial+function PDF link annotation
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/nodcgk8kvus46ul8aekldkcun4/tuminokelan.pdfIn PDF document text
    • http://caminodesantiagoenmoto.com/assets/ckfinder/core/connector/php/uploads/files/wuminujazafunawevi.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16150fc410b88a---21320082773.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/13477250045.pdfIn PDF document text
    • http://form4concrete.ru/pics/cont/file/77718279974.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/20122090108.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/tuwawupemopobamemexol.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3f63410c0---dotujawufefowotowojaje.pdfIn PDF document text
    • http://silverspringabw.com/uploads/files/nokexogabof.pdfIn PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/kofuwaxim.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/xevodu.pdfIn PDF document text
    • https://liho.cz/UserFiles/File/tejazuzilu.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/54660302660.pdfIn PDF document text
    • http://balie.overeembv-profielen.nl/upload/files/6089952088.pdfIn PDF document text
    • http://interreg-ipa-husrb.com/downloads/lepedi.pdfIn PDF document text
    • http://519pf.com/userfiles/files/vusosatofefepekebodolef.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/31053407964.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614df2f5a1436---papitatavalejevonapidoraj.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/debotoj.pdfIn PDF document text
    • https://vanchuyenduongsat.vn/upload/files/pogazaga.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/83847061809.pdfIn PDF document text
    • http://sunway.me/ROOT_PATHuploads/file/07090411699.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/3004083273.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_off00012841.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12841 11056 bytes
SHA-256: b3302aaeeb411124b0ebe69c284d9c8f2fc605133938809c0f558ed4ad3798f5
font_01_sfnt_off000141df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141DF 19760 bytes
SHA-256: 9f59a3c1184723f417a0da4ddddfbb27dc4edcd09c1a1cdb4428ab6c34d98292
font_02_sfnt_off000174c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x174C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1