Malicious PDF — malware analysis report

Static analysis result for SHA-256 9697f687e7747021…

MALICIOUS

PDF

71.4 KB Created: 2021-10-01 12:57:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: a8f26747fae1947864afa658c1fa3f17 SHA-1: 6f123bd178d59cb15c69ccd9249eed6400fd772d SHA-256: 9697f687e7747021d4af92486486028029efb669aeb5f6757945921bc1093709
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple unknown URLs, with several heuristics indicating it's designed to host malicious content. ClamAV and an ML classifier also flagged this PDF as malicious, specifically as a phishing trojan. The presence of numerous links on potentially compromised or disposable hosting suggests an attempt to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/56121353014.pdf In PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/jatabamakuduz.pdfIn PDF document text
    • http://abyss.sk/userfiles/file/zajux.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/34792835386.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/lirikede.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/vinowejono.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/laruk.pdfIn PDF document text
    • http://addon-colsman.somantec.net/ckfinder/userfiles/files/nagumori.pdfIn PDF document text
    • http://litroshaber.net/resimler/files/madekapavepez.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/zasuwejowixub.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/pufafexisal.pdfIn PDF document text
    • http://infinity-c-t.com/userfiles/file/49224279344.pdfIn PDF document text
    • https://www.poeles-granules-vasconha.fr/ckfinder/userfiles/files/meritepuzeta.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/8b29f4df4d4a12c02b346778a912c221/mukoj.pdfIn PDF document text
    • http://dae-young.kr/upload/fckeditor/file/19559120418.pdfIn PDF document text
    • http://master-br.ru/img/file/68449799303.pdfIn PDF document text
    • http://arabstina.com/ckfinder/userfiles/files/40058254721.pdfIn PDF document text
    • http://autoscuolavalerio.it/userfiles/files/6899277817.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/21264712580.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/161411e26bce73---lifijakedilaziforuxixeza.pdfIn PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/wusukejoperofusolapej.pdfIn PDF document text
    • http://portakalweb.net/home/portakal/public_html/ckfinder/userfiles/files/tekefutika.pdfIn PDF document text
    • http://mauthietkedep.info/upload/files/35157584010.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613607749dce7---dozewezuvupubezugej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=ram+rom+prom+epromPDF 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_off0000b50a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB50A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD20 9948 bytes
SHA-256: 2ee621f02cdf328cb1621125f2143fbe2ef8b973cd0737f99ae350c522c9a98c
font_02_sfnt_off0000e313.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE313 17448 bytes
SHA-256: 4da1836a9a0111fb759bdbb326db7db18284d7806e84bc6e72242f54b0af70fe