Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f9e816c09cb6686…

MALICIOUS

PDF

80.0 KB Created: 2021-09-17 12:34:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: b51873eb70bc34aef2cf2c466848a061 SHA-1: dc232a8ed8cadc22b4a8dc10b1dc86c7a24fa2f1 SHA-256: 4f9e816c09cb66864b7358588b5f5ca0e6b92fd958678ba5aba7d22023411548
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to various websites, including those hosted on compromised CMS upload storage, likely for phishing or malware distribution. The presence of embedded URLs and the heuristic firings strongly suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://crysiq.ru/uplcv?utm_term=grand+theft+auto+v+app PDF link annotation
    • https://senegal4d.com/contents/files/35309802708.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/bomaziposalokojoveke.pdfIn PDF document text
    • http://autovoda.ru/upload/files/wadexukorokenoz.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/8387132236.pdfIn PDF document text
    • https://dynasty888.com/image/files/20210901_160252.pdfIn PDF document text
    • http://spharma.ua/files/file/18644408390.pdfIn PDF document text
    • http://chiesamadremarsala.eu/userfiles/files/19005051264.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/98836170009.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161382ab3eca4f---52711779780.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/bf7d4e2dde733a40e456a0f8d8ad6abe/71344387191.pdfIn PDF document text
    • https://intekcanada.com/ckfinder/userfiles/files/16285472748.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/worexopofonetubat.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/74486124933.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/kudopef.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3d97ac96f---21193249740.pdfIn PDF document text
    • https://ixiu-23.com/uploads/files/202109060153167142.pdfIn PDF document text
    • http://www.sauminandy.com/fckimages/file/37211239836.pdfIn PDF document text
    • http://vrajacreation.com/uploaded_files/userfiles/files/kuguwimefak.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/48365477081.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/fipepasobufitamoj.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/tuwudovezakiguxuganegako.pdfIn PDF document text
    • https://notarbrazda.cz/userfiles/file/In PDF document text
    • 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_off0000d4a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB6 17852 bytes
SHA-256: 73902c589753392ae7602f579a968400eef35e437bb421a8182ea56685e2b76b
font_02_sfnt_off00011ae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE1 10492 bytes
SHA-256: 3ac05ce7f8711d7f4d6aec92cf1663f99c69257d22b82022537d9430051f8521