Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d90f383ae82ead4…

MALICIOUS

PDF

90.5 KB Created: 2021-10-30 07:38:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 21cebde5ef0c6cd05486f9028e6fc2b5 SHA-1: ee1022cd9ffbd07b8b633817867a1dab154a42a5 SHA-256: 7d90f383ae82ead4f3755d613fa64145a025463fa0d548d468fbdec428a2c8ec
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised or disposable hosting services, likely to distribute further malware or conduct phishing. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights the non-clustered nature of these links across many distinct, potentially disposable hosts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 6

  • 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.
  • 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://polytex.de/sites/default/files/gezegikaxewujodir.pdf In PDF document text
    • http://grupafurman.pl/!mag2011/userfiles/file/rusitebunimoder.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/5279246221.pdfIn PDF document text
    • http://vividconcept.in/userfiles/file/fotajuduri.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/b07c5eb3e7adc438dd64d3c94c740726/53184363086.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/4808833137.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/3072748322.pdfIn PDF document text
    • https://eurotig.ro/file/lagapaj.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/3246567110.pdfIn PDF document text
    • https://ladachess.ru/userfiles/file/21844057133.pdfIn PDF document text
    • http://khachsansapa.vn/webroot/img/files/rerokor.pdfIn PDF document text
    • http://koutingchina.com/upload/files/xuperadotad.pdfIn PDF document text
    • http://kor-ra.ru/UserFiles/file/55913887065.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/b28bbe6d322019fad1633509e9e846d8/lipavitug.pdfIn PDF document text
    • http://93564497.com/userfiles/14892879175.pdfIn PDF document text
    • http://villamishkan.com/310renonew/front/images/files/ketokip.pdfIn PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/pofol.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/37210728769.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/kjv4bsl7oi8d9un20v5gsj6uk0/kukesememugefokizoba.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/26091966273.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/4a56d56be8fafd04b68e15f44457e3ef/23142701777.pdfIn PDF document text
    • http://amdind.com/userfiles/file/49204409611.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/93617742289.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/vipisijebi.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/mabitinumafokodunupi.pdfIn PDF document text
    • http://pbpharm.com/upload/files/42149498427.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/1hHberoKktI/uplcv?utm_term=chest+tube+management+powerpointPDF 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_off0000f586.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF586 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D9D 11012 bytes
SHA-256: c199bb4b9a1d23aa33a991fc728f8f23cd483fc3efa7996fe5af23e91ca7131b
font_02_sfnt_off000126e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126E4 20752 bytes
SHA-256: 1d6401e51f815fecb68dcfcdbde4f2943564125c459eb5a3339fcd65f98ff06f