Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4f05e935b98f4d6…

MALICIOUS

PDF

77.9 KB Created: 2021-09-05 07:18:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e5b3d0854c7a6165ec52b0ab0969fffb SHA-1: 951e38d163f27edf7d49158ee653ab53850755df SHA-256: d4f05e935b98f4d6b24bbf9e680c4b1538202ccac8adb85831bf75b3e12fdea9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and URL analysis strongly suggest a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://studiofelician.com/userfiles/files/77632792716.pdf In PDF document text
    • http://uleshuzatshop.hu/files/file/wuxam.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/wubevogeputovor.pdfIn PDF document text
    • http://alwaditrading.com/userfiles/files/68510982642.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/dirugutagaxorukuze.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/29177386116.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/71ecb41ca27715f7d2032a3335793cad/tilifi.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/86593378818.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/82755125644.pdfIn PDF document text
    • http://lyzebrno.cz/userfiles/file/48858748137.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0518be7e5---15055456240.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/95048243607.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f4072d6a4---dotijedokexudidij.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/12728542620.pdfIn PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/kavubijo.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/cfda9d80c25aba7ff34610ffd6904cf7/wiwizaxoregijuloj.pdfIn PDF document text
    • https://soechi.net/userfiles/file/wunimipalobuzuret.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/wowajezinipawetunuvo.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/dg1booq8efhj9vsbgcpfopdsru/95843335169.pdfIn PDF document text
    • https://www.bistro-e.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b386e9c8e2---13293466830.pdfIn PDF document text
    • http://canigrup.com/userfiles/file/bakokejisiwujezipiloraz.pdfIn PDF document text
    • http://miamiokclassof65.com/clients/d/db/dbefc63a503cf3d3a4f9fb61678ecc08/File/gipavusisubivabexegujan.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbed6597363---kapogozez.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=mean+median+mode+range+worksheets+grade+4PDF 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_off0000cc95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC95 16948 bytes
SHA-256: f77b238030969acca0caa69eec68e7dca4cb28341160492865fd9e29f73fa97c
font_01_sfnt_off0000f84e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11065 10900 bytes
SHA-256: 72eb737023575a676cd358f85d659f9cc46f18f70941445bd86531ea9c49a09d