Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cf59262737dcbd0…

MALICIOUS

PDF

94.4 KB Created: 2021-09-15 23:57:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 3d747a4c9a498a5d7af11cacac3b86e7 SHA-1: 264b23418953df071727f44dc7f3a59baa2c9f29 SHA-256: 8cf59262737dcbd01527455e319837d06a2a090c6217e291e046122bd255de99
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, indicative of a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URLs are sufficient evidence of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://nomylo.ru/uplcv?utm_term=the+perks+of+being+a+wallflower+novel+pdf PDF link annotation
    • https://licorne-hotel-restaurant.com/userfiles/file/23187593684.pdfIn PDF document text
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/zutitigimekewekavojew.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/sagosekuxujixutanurewa.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/telekowapunavudexebosup.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/0120ebc70dfb4f2e4e59bf51f8b022c8/36941798456.pdfIn PDF document text
    • http://mayingiabao.com/upload/files/lofekajun.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/zakedimemifovixel.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/ratozomavana.pdfIn PDF document text
    • http://vdtonline.vn/static/uploads/editor/files/vuzusedafunegi.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/58147894488.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/vakezovupuz.pdfIn PDF document text
    • https://777mto.org/contents/files/31663352382.pdfIn PDF document text
    • http://n2nlah.org/UserFiles/file/donegirivukized.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139780430999---bomire.pdfIn PDF document text
    • http://mijinmotor.com/fckeditor/userfiles/file/piwimonuxopemejuzeta.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/145d5175651046982edc78c16256d011/67256154125.pdfIn PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/rizanumime.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/kurikitetetuxi.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/megosojerazawatogidak.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/98505222800.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/nuwipolidodepal.pdfIn 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_off00010990.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10990 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000121a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A7 11028 bytes
SHA-256: 30a9779d00afb2480708bf070fa5b072f3152a66948f1a4fa7c61a119a1c3e5a
font_02_sfnt_off00013adb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13ADB 18744 bytes
SHA-256: 2eb4223412ad54f0fee5d4e2f3bf6363fcf17953d1ef540033d6a582733dec76