Malicious PDF — malware analysis report

Static analysis result for SHA-256 356390abd004c739…

MALICIOUS

PDF

67.9 KB Created: 2021-09-22 14:30:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 93948c782cfcfd2ea7a35c7511bcb5a5 SHA-1: e51fd6b1e35d0fe19b62bf99dc9529b0c95be6ab SHA-256: 356390abd004c739e3cb901568013244b3de900852e5706915bda3a8aa8c6fbd
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple PDF files hosted on various domains, with some links pointing to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristics and embedded URLs suggest a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://euromarkcreations.com/new/fck_img/file/24337710627.pdf In PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/62140796348.pdfIn PDF document text
    • https://tssch.in/tssch/application/admin/uploads/file/fokojokurokajesa.pdfIn PDF document text
    • http://mim2010.ru/userfiles/file/85832940640.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/95138492004.pdfIn PDF document text
    • https://termokingbt.com/ckfinder/userfiles/files/38134840409.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/8dcc3b4ad793f331d5f6cebebb4eda3a/2252502337.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/vewivaxokezilela.pdfIn PDF document text
    • http://fitviewer.com/files/file/57811129091.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/fedowidovukulutamuluno.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/zibivukikegos.pdfIn PDF document text
    • http://ggmtc.net/userfiles/files/pategobunalutinomerubusa.pdfIn PDF document text
    • http://partnercable.com/files/bazeved.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-2/20210902212818451630.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/jenavulojewatizexuseti.pdfIn PDF document text
    • http://lindendirect.com/tempimg/file/fewaga.pdfIn PDF document text
    • http://etalentlink.com/uploadfile/file///2021090408101137.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/54282173822.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/9142290570.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149959c9fc37---gizak.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a44ff6ff4b---36412152349.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/71490993551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=plato+game+iosPDF 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_off0000ae0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c61f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC61F 14856 bytes
SHA-256: 50207cc604f78be1f479a9668ba00456c31d70e67c87b38fe311d6b48fbfe874
font_02_sfnt_off0000ebc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC0 10248 bytes
SHA-256: 99153ed1196e3ace1cce1f80f6a59cb4be3b5285d677eef4fbb4bf98645a21b0