Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e71955a3c839646…

MALICIOUS

PDF

83.6 KB Created: 2021-09-13 21:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ce34f9f8db24d7aef56bff226ba3365d SHA-1: 3cbd93e0698bb148a81cb0a9e9172fc7b974dba3 SHA-256: 6e71955a3c8396464a6d9ba4107157f87ce94a59138029db0556d03b048bfaf4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the heuristic firings point to a malicious PDF document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7876411ae---zotomazina.pdf In PDF document text
    • http://brukikostka.pl/uploads/page/file/7056331711.pdfIn PDF document text
    • https://upaspor.com/resimler/files/2247439509.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/sadirizopoxuvexukon.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/rekojoweparikuruwedupo.pdfIn PDF document text
    • http://rsentco.com/upload/file/42408780055.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/webakukamogeg.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/59374500461.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/e4f9349ddd69fc855f7471a1837277c5/detumokaramipezekiju.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/tojagigepakibenaf.pdfIn PDF document text
    • https://alienaquatics.com/home/gb/public_html/ckfinder/userfiles/files/gegamexerujugekurarale.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/380a5080d69e8b3b4a9acac683c5e9ae/tifojekibepanot.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/74016351355.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/6774269459.pdfIn PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/vivijotivafimuni.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/85984403628.pdfIn PDF document text
    • http://intertravel.hu/_user/file/nuwanozorowi.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/30938895386.pdfIn PDF document text
    • http://ticketsperiodico.com/galeria/files/75090588555.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/zefokes.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/fatisidojeg.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/muwekajumax.pdfIn PDF document text
    • http://optykglowacki.pl/obrazki/files/zilunivuweresuwilisoken.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=recupero+dati+da+backup+androidPDF 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_off0000e0b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B4 10672 bytes
SHA-256: 8f9d2646721f9fe993747d69d890ae9d44ead11347bf9852e92230caf2717e60
font_01_sfnt_off0000f909.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF909 18436 bytes
SHA-256: 00aeed6716a450f849453e2479318d1541d8c862b1e69f7ea9f5bc4868aa94dd
font_02_sfnt_off00012917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1