Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fd29c05e500d393…

MALICIOUS

PDF

119.4 KB Created: 2021-07-24 10:28:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a1462107b775001ac3ad150185b34be4 SHA-1: 8528927aeb026834c09de70bef24da7ca65e69a2 SHA-256: 4fd29c05e500d393a9b279e5f490feed2987dcd328ae43899fffc43de9485fc7
156 Risk Score

Malware Insights

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

The PDF was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, many of which are associated with compromised CMS uploads. This suggests a phishing or malware distribution scheme where users are lured to click on links that lead to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://mhinflatable.com/upload/file/85673937372.pdf In PDF document text
    • http://myucmas.com/userfiles/file/19795802354.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608094a5df9dd---xojutalunanikowuz.pdfIn PDF document text
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/93930872636.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/bafafapupisitiminagutilef.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/c0f7crsu787h63c120bo1svk8s/95377713548.pdfIn PDF document text
    • http://alliusie.com/userfiles/file/8401463760.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/76248882557.pdfIn PDF document text
    • http://texasstatealphaxialumnae.com/clients/f/fe/fe72632f573fdc77cca6b85875c63e8a/File/47339909388.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/47c52cf6d0d8cfb3e468cf92d06320cc/sezalukefigi.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609dbfc40eb57---79277657655.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/46388371408.pdfIn PDF document text
    • http://timnhanhonline.com/upload/files/fazupumawate.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a428a8cd023---76343370951.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef38c5f2e6---pawajupadukibikezizup.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/reruwadol.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/a3fe51910fc00b4aef40fad561be2c01/79782350117.pdfIn PDF document text
    • http://aromaonly1.com/yamituki-n/uploads/files/49199144987.pdfIn PDF document text
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/95071af86edee96031c53315346e3d98/76297141787.pdfIn PDF document text
    • http://weddingdiy.cc/uploadfiles/files/20210609_095303_1740.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2lvkr8dngd9otro8e2nu31to60/88900096325.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/1786317874.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/c9e6bi57pbhub82iesnhg5eicc/92288464139.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160afcbda2ce7b---14418339307.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=what+is+ironic+about+the+song+of+the+thrush+in+the+darkling+thrushPDF 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_off000170e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x170E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000188f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x188F9 11080 bytes
SHA-256: 61b61125c6b6efb33a22285820200c4accc435303ef68de5f03cfa70bced113d
font_02_sfnt_off0001a290.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A290 17032 bytes
SHA-256: 5da14ba1c7c904f62f7f517f73ba01c37f8bab766e501c5cb0d07c42b3b5ee1e