Malicious PDF — malware analysis report

Static analysis result for SHA-256 b169abd7d5fcc660…

MALICIOUS

PDF

76.7 KB Created: 2021-09-19 17:29:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: dd22b09a786a903be663490311a8f19a SHA-1: 3ba1ea83c81468b2f923ed585e1df3575b1c43c9 SHA-256: b169abd7d5fcc6606a720e3c2601264d50192b9906e799fba6013a93e4108031
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to lure users to malicious content. While no scripts were directly extracted, the nature of the embedded URLs and the PDF's structure strongly suggest an attempt to redirect users for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://4grd.com/cmsimages/file/68275162105.pdf In PDF document text
    • https://cornwallstaffagency.com/userfiles/file/liregerekujefalabexa.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/50270332155.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/fudobetotazefatidab.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/letarit.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/46162101583.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/70969414126.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/82351894754.pdfIn PDF document text
    • https://sarvodayasamaj.uk/upload/files/dapuzexusazitesutolu.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/sokejugagiporajodofigigo.pdfIn PDF document text
    • https://dynasty888.com/image/files/20210919_020159.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132856eb737d---natupesegivebonubusini.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/22400603315.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/26874652116.pdfIn PDF document text
    • https://doanhnghiepvietnam.org/img_duhoc/files/66401173260.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/mej2d6nodfnfnk8u6edoetkh76/pitawimuvanuleb.pdfIn PDF document text
    • https://kiaavcilar.com/upload/ckfinder/files/zujadusalozowumigoso.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/ritebef.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/96078671634.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137812e4b883---67985053631.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/23020800409.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/lesetajojitef.pdfIn PDF document text
    • https://cheesykeju.com/contents/files/20798465655.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=retrofit+in+kotlin+android+examplePDF 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_off0000c794.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC794 10728 bytes
SHA-256: 12e474d494ed972a2227e9b7943a693de5f553146799798d8a6e9c514ebbb4af
font_01_sfnt_off0000e029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE029 17076 bytes
SHA-256: c64364ae11c686f57c40a667ddfc0eb4665555643cf124e9975426063798b549
font_02_sfnt_off00010d2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D2D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1