Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b6247ea2eecaed9…

MALICIOUS

PDF

71.3 KB Created: 2021-10-02 17:17:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b2b4f50fde2a9424ea38f13b4dd2e952 SHA-1: 20e5e01c1e04a27b7433fae3cc640dcf2ac43131 SHA-256: 9b6247ea2eecaed962b8dbedc24fd1ac3977d4bc08215d454f4485d611e18286
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF contains a link farm, with some links pointing to compromised CMS upload storage and others on disposable hosting. The embedded URLs, while numerous, are primarily used to redirect users to potentially malicious sites, suggesting a phishing or SEO poisoning attack vector.

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 http://kemnhapkhau.com/upload/files/sozosewuwixamiredoxi.pdf In PDF document text
    • http://schokoladenbrunnen.de/idata/437134016.pdfIn PDF document text
    • https://tagoproperties.com/ckfinder/userfiles/files/97376833993.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/70215003950.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/zobemobinak.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/nelukutabexaguzusajateto.pdfIn PDF document text
    • http://dtpokebar.com/uploads/files/rasikibigugakudo.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/kobinejosebe.pdfIn PDF document text
    • http://farmandari-sarvestan.ir/images/news/files/73149901408.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/83600909974.pdfIn PDF document text
    • http://rc-saty.cz/gais/image/file/97551122313.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/45152449669.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615854f9efef0---farowurafebi.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/3646363755.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/49169708577.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/gilidadadobanadereroki.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/6313039495.pdfIn PDF document text
    • https://generalaudit.pl/eurostyl/photos/file/noxogutudiwofabegaju.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/2oj189i7f5j66gvv1q7a6plir5/26482480166.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161508bfba3290---bemidebezenupi.pdfIn PDF document text
    • http://runhouchem.com/upload/files/powunekonafigutaval.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1615614005e011---fakiresedor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=nand+gate+latch+truth+tablePDF 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_off0000b3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DD 17088 bytes
SHA-256: 6ff5616738edb4253b63b397a0601904b904c303924e6a4d0700db6be8f4cdf5
font_01_sfnt_off0000e00c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00C 10484 bytes
SHA-256: fca146865b5e7e3b10a2a9952a74db8275c174a83bbd20dc7cf6da709765ca61
font_02_sfnt_off0000f793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF793 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1