Malicious PDF — malware analysis report

Static analysis result for SHA-256 98c51a22590e64ff…

MALICIOUS

PDF

79.7 KB Created: 2021-09-24 11:53:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6026e551d2fee909890ee351ae7fc9a5 SHA-1: b9dbae7263eac07ac4a3f4535404b82a9ced26b2 SHA-256: 98c51a22590e64ff07975700a67f47511e65e06c8018aa03b0814d10b780e17b
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs that point to potentially compromised websites or disposable hosting, likely intended to lure users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using non-clustered link farms on disposable hosting for SEO manipulation, further supporting the phishing and malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://lsneotek.com/ckupload/files/babobopebinilutotubejifel.pdf In PDF document text
    • https://aventura-agence.lu/userfiles/files/zebagumuxidiwazomisek.pdfIn PDF document text
    • http://tiszaladany.hu/upload/file/21011880161.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/276147206.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301ef55a8a6---75108154100.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/95618834720.pdfIn PDF document text
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fenazufebogu.pdfIn PDF document text
    • http://union.travel/ckfinder/userfiles/files/20411364491.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/31428106730.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/72459891166.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/87952365334.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/nakusibix.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/76996338552.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/96444248872.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/ribiwakasaziririjazuke.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/5839830171.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/20870863772.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/0cb5ba8072f4989592a0cabe1a69d61e/gorimolagududafegexen.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/10942826594.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/23955994918.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/77622721873.pdfIn PDF document text
    • http://bennett-legal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nukubopukenepekunefiba.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ae3afd7695---wesajatomesofekaserobike.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210909211933.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/74882924205.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=generic+structure+of+analytical+expositionPDF 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_off0000d53e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED55 10828 bytes
SHA-256: 4676d6b6e9214a4de8ecd994e137c0349c54edb69b2f486f0969ea896bfddcd6
font_02_sfnt_off0001068e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1068E 16752 bytes
SHA-256: 4b3bba652e1cfb80d4a46d3cf0d5da8aee7c0e4bcb5d74bb61150a245d603dc2