Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec372ef87a0e02ef…

MALICIOUS

PDF

76.6 KB Created: 2021-09-16 12:42:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b05ff403602a949db7df38294d823312 SHA-1: 83f132b9bf6eeae622abbcd9201fa9c57addc818 SHA-256: ec372ef87a0e02efb6f05b5b09bd1e48de45a25bc2e1357a59ad059e7a143706
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 an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. No scripts were extracted, but the overall structure and heuristic firings strongly indicate a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://avvolodin.ru/upload/file/11681190924.pdf In PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140912b8200f---6953265016.pdfIn PDF document text
    • http://baloneacessorios.com/_upload/file///98477932967.pdfIn PDF document text
    • http://czechdidgeridoo.com/admin/upload/file/rokuroratubokibopizama.pdfIn PDF document text
    • http://hacsbathtarntaran.org/~/userfiles/file/78762503799.pdfIn PDF document text
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/52998820430.pdfIn PDF document text
    • https://anup.bo/images/files/kazirewexevusixerevesaguf.pdfIn PDF document text
    • http://hermanosgolbano.com/admin/fckeditor/editor/filemanager/connectors/phpfile/36180367996.pdfIn PDF document text
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/78336189150.pdfIn PDF document text
    • https://gencatakan.com/upload/file/5397469285.pdfIn PDF document text
    • http://irinaburmistrova.ru/files/75405321322.pdfIn PDF document text
    • http://maybaobidinhdinh.com/upload/files/nozagirij.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/60472672180.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/22021758857.pdfIn PDF document text
    • http://sinoorchids.com/image/file/buvoxifopa.pdfIn PDF document text
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/41677896579.pdfIn PDF document text
    • http://monticellotownship.org/userfiles/file/65670956896.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/4as91hqi2hquco091o7jtb7aur/57056010698.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/ruvajivuwagigomivi.pdfIn PDF document text
    • https://arslanemlak.com/E/file/In PDF document text
    • http://cmtl.in/uploads/userfiles/file/file/3484737256.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0a0be107a---nudalamotixan.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/vulenizumogegis.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/35645188103.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/fasuboxapagodubofunekas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=cwm+installer+apkPDF link annotation
    • https://b2cdemo.tickets.com/content/files/67506410343.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_off0000c768.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC768 17400 bytes
SHA-256: ca4182aadf87f358d34f6afdadc0aca3a75dad62eacf50366c13b3fc2de7a3e5
font_01_sfnt_off0000f49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF49E 10500 bytes
SHA-256: 3e65a2b3a964ade83c4962bb9e100d2a7df9538442165d2c78c7f84acce01a57
font_02_sfnt_off00010c86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1