Malicious PDF — malware analysis report

Static analysis result for SHA-256 51dfcb08843ac54a…

MALICIOUS

PDF

79.7 KB Created: 2021-09-15 22:25:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a4a66975216225f3e237b14189b4eeb4 SHA-1: fc17c25b65996ceda4f4c27afed18735666c5dec SHA-256: 51dfcb08843ac54ac209943e0da4c02bbd43a3f7c74467d75b2755fe03e3d302
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external links, many pointing to compromised WordPress sites, suggesting it's designed to lure users into clicking malicious links. The presence of a 'Fake CAPTCHA' heuristic strongly indicates a social engineering tactic to trick users into performing an action, likely leading to further compromise. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=gta+5+apk+without+phone+verification PDF link annotation
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/pdaqpha9ce7m0as8ehlhot30id/65158033055.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/gunozezobe.pdfIn PDF document text
    • https://globaldreamindia.com/webcms/file/vufapawafakafamaba.pdfIn PDF document text
    • https://podiummagazinenews.com/ckfinder/userfiles/files/juwipari.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/188de9b7a5ad0fd0dd39b4580c437de5/20361910035.pdfIn PDF document text
    • https://qigoodteam.com/uploads/files/202109071230171523.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/df00d327d3b358255aeb6cca48f14e9b/vebiwulagufaxopejot.pdfIn PDF document text
    • https://steammining.com/userfiles/file/67892670187.pdfIn PDF document text
    • http://uniradioweb.info/userfiles/file/59947394389.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/47959067572.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/nerebemadirafazax.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/49193567845.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/nipev.pdfIn PDF document text
    • http://amandamaitland.com/images/file/47267135588.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021090212562947.pdfIn PDF document text
    • http://peak-experience-europe.com/images/blog/file/79460526455.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/80142319936.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359f6f8414d---damigaditeg.pdfIn PDF document text
    • http://paintmaster.hu/js/ckfinder/userfiles/files/30228344660.pdfIn PDF document text
    • http://carrozzeriabosini.net/userfiles/files/80135659859.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/80881312648.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/fameguz.pdfIn PDF document text
    • https://matkinhantai.com/luutru/files/37691279161.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613148736ca7e---vusavejafate.pdfIn PDF document text
    • http://chipgene.com/image/files/20210903_081004.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_off0000cfe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFE7 18212 bytes
SHA-256: 3e70c949f4706c3c95bdaf4a1b9812b21cd5cbd035e57149d07c6f579f5b9a63
font_01_sfnt_off0000ff4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF4D 10880 bytes
SHA-256: 0a23abb485b76467216af3dda0f0aba2ce0b7f77cc17a3e4592cfb0be176c035
font_02_sfnt_off00011895.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11895 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.