Malicious PDF — malware analysis report

Static analysis result for SHA-256 80b71debc4461e7a…

MALICIOUS

PDF

70.9 KB Created: 2021-09-13 11:08:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6b1620a3afbd8b3133f172a53803578a SHA-1: 0aa71a90b90f49fd852f38be80d7d8883566c653 SHA-256: 80b71debc4461e7a891a807f33f8a33de0fc24e998e05c2b6312368e273f498b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites. One heuristic specifically identifies it as a 'PDF link farm points to compromised-upload storage'. Additionally, an embedded JavaScript stream was detected, suggesting potential for malicious scripting. The combination of link farming and embedded scripts indicates a likely phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://chcial.ru/uplcv?utm_term=my+public+wifi+for+android PDF link annotation
    • http://bagliodeimille.it/userfiles/files/bezukul.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/dexabutugavipan.pdfIn PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/36600277717.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/91349686396.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613301fe4e025---15733626976.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/tevodaniwuwubejusekereke.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/bepewuwekavutewivivotug.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/dijozisurajezalope.pdfIn PDF document text
    • http://wdnederland.nl/file/35142105252.pdfIn PDF document text
    • https://henseltech.cz/userfiles/file/41295116095.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/896v09c6ih1m825cvjlr8kcfp4/lodefepitirofejid.pdfIn PDF document text
    • https://meritumptt.pl/dokumenty/file/73843409900.pdfIn PDF document text
    • http://afro-safari.com/upload/files/5383308877.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/ketujozakedunuvagiwuzad.pdfIn PDF document text
    • http://ventiliatoriai.lt/js/ckfinder/userfiles/files/rosusama.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/sufubejazujodijunin.pdfIn PDF document text
    • https://shipnhanh247.vn/asset/files/girulisanadeduxurer.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8a22b497f---guxavafefimedolab.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/84967813131.pdfIn PDF document text
    • http://montpellier-businessplan.eu/mbp/upload/images/images/upload/ckfinder/potozegofopuri.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_off0000b27e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB27E 10648 bytes
SHA-256: d56689a23fa2a0c0c7add0124413b823bf065b352691342a84ba71d368348b10
font_01_sfnt_off0000cabc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCABC 16736 bytes
SHA-256: f8a60f21c7ddbbcf2c6496fbc5173da084358c8e174e9cfda6794cb93a1a42f2
font_02_sfnt_off0000f5c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1