Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c8fc1c2c4a48760…

MALICIOUS

PDF

85.0 KB Created: 2021-09-17 18:25:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4f9cb5509a6ef9d198cc282daa2e33f3 SHA-1: 0703aedbb759820803f9194467be8e5912e608aa SHA-256: 9c8fc1c2c4a48760152a6b0798322e1f1a22b17586de28dfc6ced9b19f811928
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary attack pattern involves directing users to external, potentially malicious websites through a collection of links embedded within the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://hanhthien.net/uploads/file/rezasunuxawop.pdf In PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/pozozefolej.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/25478106304.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/busepit.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142781aa0761---gesosuzobigajatetev.pdfIn PDF document text
    • http://plaschke-partner.com/uploaded/file/13366514173.pdfIn PDF document text
    • http://fmi.lu/userfiles/files/ravedenebeboriwu.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/mujosutapalalasure.pdfIn PDF document text
    • http://thuaphatlailongthanh.vn/upload/contentFile/minhchau/file/keguvefaxiti.pdfIn PDF document text
    • https://bomando.bomsolar.com/uploadfiles/files/siwixesedozoxujadid.pdfIn PDF document text
    • http://nanoservice.cz/upload/file/25538618200.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/61686010674.pdfIn PDF document text
    • http://poledance-chrudim.cz/files/file/rixituketelew.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/litixo.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/e5de44d306cbc2453e127399f7946161/39651591861.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202109151221031936.pdfIn PDF document text
    • http://ricoconsultingattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kefipaxorofuzuvo.pdfIn PDF document text
    • http://dongtienlamnghiep.com/upload/file/fonibodevoxosezuwuzu.pdfIn PDF document text
    • http://duocmyphamcongty.com/app/webroot/uploads/files/wovanixipunulin.pdfIn PDF document text
    • http://aostavet.it/userfiles/files/9269691816.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/2817770143.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5f70a870d---jonux.pdfIn PDF document text
    • http://penzion-u-zamku.cz/files/file/bubunajawawupubomojenag.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/35560100747.pdfIn PDF document text
    • http://adbuilder.at/ckfinder/userfiles/files/rireruxazimefad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=sms+blast+apk+2020PDF 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_off0000e833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE833 17860 bytes
SHA-256: b6a80845cf31d1a584fa7c9c4b32e6788c56cfaa8d050dc1e83320e8baad4862
font_01_sfnt_off0001168f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168F 10412 bytes
SHA-256: 189d2594fcf764dd0998a6d3ddbe31a74cc178fac5ec7a1c00946ff281cbde06
font_02_sfnt_off00012e08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1