Malicious PDF — malware analysis report

Static analysis result for SHA-256 068f52a4f4c665bc…

MALICIOUS

PDF

84.5 KB Created: 2021-08-04 01:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e3e7671f6d6d9435e567e73a383a6e2e SHA-1: 05f1385854eebf9e350e9f687a764983fca8b3c2 SHA-256: 068f52a4f4c665bcce911b9a36f4c3142c669f12cab46d34749e35e9db3c6452
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the PDF is part of a link farm, directing users to potentially compromised or disposable hosting sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://hiddencliff.kr/FileData/ckfinder/files/20210716_BD62EE386E248BF6.pdf In PDF document text
    • https://callalilyvn.com/upload/files/tososonal.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/os6an8pbisgb2hsppcmm8phu8a/15646969925.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a37dcaf39---bifekodisexen.pdfIn PDF document text
    • http://learningkey.org/userfiles/68547518365.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/ca7c79a9c3095a64ae623e8468b7e514/86803460065.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608e89845651c---93530432610.pdfIn PDF document text
    • https://liderpin.com/calisma2/files/uploads/16379920720.pdfIn PDF document text
    • http://stadion-zarya.ru/ckfinder/userfiles/files/41610216992.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/sba66tfhqh8gvp2g0o19dncmmn/94435792541.pdfIn PDF document text
    • http://orourkelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9169178581.pdfIn PDF document text
    • http://dongkoo.com/uploads/editor/files/duxerobelujer.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/54786095171.pdfIn PDF document text
    • http://insidethedigitaltrend.biz/userfiles/file/34492169318.pdfIn PDF document text
    • https://pjkconstruction.ca/images/file/55427713107.pdfIn PDF document text
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210704071241617215gleo9t.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7901063202---2845745503.pdfIn PDF document text
    • https://cvconstructionsgoa.com/pharma/admin/userfiles/file/49053261687.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=what+is+faster+payment+on+bank+statementPDF 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_off0000e7f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F6 16892 bytes
SHA-256: 4ce4ed6572b037671fdac14d7513578597e46e695fd7e890e3c98ae174b1a513
font_01_sfnt_off0001140e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1140E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C25 10916 bytes
SHA-256: ba56b716838d003339ffd639c0622a097830930b3f1937306b6e6f8987640a86