Malicious PDF — malware analysis report

Static analysis result for SHA-256 933e00f14c2311c7…

MALICIOUS

PDF

86.7 KB Created: 2021-08-10 09:25:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 22cb4f493a633d4c04fc0b973f58689a SHA-1: 44c860c05e002e7df10b3aa8950e04fe70b2f461 SHA-256: 933e00f14c2311c738f496c3e753eb47a4952f1e207d021ca857b0a9c35269e8
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a tactic to distribute malicious content or manipulate search engine results. The embedded URLs, while some are marked benign, contribute to the overall pattern of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/lmi6087dnhagdr4qfgmc9bsco2/fobek.pdf In PDF document text
    • http://sovaimm.it/userfiles/files/99556337496.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/sujaro.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/33456094220.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/47556230183.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/dolelumaredinoxaxeda.pdfIn PDF document text
    • https://gozdemsigorta.com/hulya/upload/files/zenefopafolotufubivo.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1556a47f0---fuzuroniziratonox.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16074426023742---tugozejudojeje.pdfIn PDF document text
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/ddbf770a4a99f9dc4a26098f62c5d16d/28646033018.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/4f55bd318b393e9c8b8d81f79b19f12e/togegaga.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/79598445345.pdfIn PDF document text
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/86bb136fca145ddac99902ef2df02afc/87705978791.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b95c28e7c---kabaxusozulebitodije.pdfIn PDF document text
    • http://msinziniering.com/userfiles/file/resuziwategudonu.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/sanijafoxe.pdfIn PDF document text
    • http://greenplanetnepal.com/userfiles/file/rasomemavuxomefateso.pdfIn PDF document text
    • https://tanhoaphat.vn/userfiles/file/21018601876.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=ielts+reading+heading+matching+practicePDF 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_off0000edc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC8 17356 bytes
SHA-256: d40d71efd81717523935055049d276343f1b0e598edb59423b00feee5481d251
font_01_sfnt_off00011a8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A8B 10792 bytes
SHA-256: c4138f2f35d33e465713983903fc7268bd5f6d8890fff0a54d66003f1a554b17
font_02_sfnt_off000132f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1