Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b2aa3b1f3b018a…

MALICIOUS

PDF

73.8 KB Created: 2021-09-14 04:35:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ebf10cfbc2684677b23ca992a954adaa SHA-1: e76e257a0133e6566c7fba2b5bb07ab8a36c4a66 SHA-256: 37b2aa3b1f3b018ad23171ba2d78f7dc3552cd71b992dbd9b7bbf856fc6d1bd7
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised. The presence of multiple external URIs and link farm indicators suggests an attempt to distribute malicious content or phish users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://autofox.lt/ckfinder/userfiles/files/memobefedodopazif.pdf In PDF document text
    • https://eslms.com/userfiles/file/pifapomesigavuvigiwo.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1613e680be5862---tizesatogepas.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210905183713.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/86555251744.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/rikugevozekosatokiwivir.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc3c361dc1---51495836916.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/fuvaxopifasudegasof.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/demonebobibetizez.pdfIn PDF document text
    • https://europawindow.com/app/webroot/img/main_content/files/2962488018.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329a7b8813c---gagivapakubiv.pdfIn PDF document text
    • http://www.parinet.fi/tiedostot/files/forawal.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/nodevufasusibutola.pdfIn PDF document text
    • https://ketex.com/trcgp/ckfinder/userfiles/files/moresetoxarikibupugom.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/7b5b56225ac14e2e5cbcf16c1cf04372/figulaludekaxixaw.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/loteboje.pdfIn PDF document text
    • http://nhasachnguyenvancu.com/Images_upload/files/pipokatijamug.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/50187055010.pdfIn PDF document text
    • http://eastindiaspray.com/suvra/eastindia_spray/files/54174723002.pdfIn PDF document text
    • http://proficlim.ru/public/userfiles/file/16878218208.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/91022172598.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd951cac59---korekidutuvilav.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/lbrljren9v2ljm6ch5n14gda80/dimazuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=skin+tools+pro+free+fire+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_off0000bfc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFC1 16172 bytes
SHA-256: 0021c475365425ae14fc35ae389208c042615ac33e6ff838f9c289d6dfcb30f4
font_01_sfnt_off0000e8ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10105 10744 bytes
SHA-256: 60cdb2a7e2314a4f7544890c028f9c46e43b499e3988e5e556e115700b39ea00