Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a915bab7797b4bf…

MALICIOUS

PDF

73.1 KB Created: 2021-09-14 21:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6e13d5e1b933326a5cb30c3c8cc67c33 SHA-1: a6f173cd1a12db9b604d3d208967baaa5fca3858 SHA-256: 9a915bab7797b4bf2a37e28b9c6becc8f81b254c944f982a8a5fabca4dc35a89
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on disposable domains, with multiple URLs pointing to PDF files, suggesting a phishing or malware distribution attempt. The presence of a link to a compromised WordPress upload storage further supports this. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://ketoanantamhcm.com/uploads/files/2982898788.pdf In PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/nosepuworono.pdfIn PDF document text
    • https://gencatakan.com/upload/file/notagitulax.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/65147279015.pdfIn PDF document text
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/77714462733.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/tatozelukepexodekulewejut.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/mekeginazivewu.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20210912033540501.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/runolun.pdfIn PDF document text
    • http://iucecb.com/files/file/daramozafug.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137387daf353---6645817260.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109060045267992.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/nuvilizezadorumeguxebaj.pdfIn PDF document text
    • https://derya.afmiletisimajansi.info/resimler/files/zesuxeneboxodune.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/12458386769.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/tupaxufimor.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613195888dd1e---genezejorasij.pdfIn PDF document text
    • https://bimore.vn/webroot/img/files/44871221401.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/79911004742.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/f09bba51ee27dfb1fabab5b563d3b9ae/pisus.pdfIn PDF document text
    • http://jindi2010.com/uploadfile/files/rusiwasota.pdfIn PDF document text
    • https://jphotographyllc.com/userfiles/file/85147061286.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/f9b4d36ed2f223b3056686c748b2ab9d/53034375585.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/futabepulifejes.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/18148475297.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/59459951080.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1b7836e9d---10761107612.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=world+box+premium+apk+downloadPDF 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_off0000bacc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBACC 10800 bytes
SHA-256: 4720695528bde01c33a029171a4d9e130d0e21913dbfe9e61bda31f360621e4f
font_01_sfnt_off0000d365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD365 16232 bytes
SHA-256: f353c8617087819d3e586c87dfe617e019cdd1c5e99f9810e588db27c766152a
font_02_sfnt_off0000fd66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1