Malicious PDF — malware analysis report

Static analysis result for SHA-256 639b130aa54b1ebd…

MALICIOUS

PDF

79.7 KB Created: 2021-09-06 20:45:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: f695731ad731d2d3eec045623dabd0a6 SHA-1: 83645352652dcd1f9e6173f61ada0d85101d96b1 SHA-256: 639b130aa54b1ebdce9b2d0c5f9ad401495a4853fac02a54174e363fa8989fee
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://laborke.ru/uplcv?utm_term=fraction+decimal+percent+notes+pdf PDF link annotation
    • http://obras.ru/sites/default/files/uploads/vipupuwilusux.pdfIn PDF document text
    • https://civilkontroll.hu/uploads/file/13049860460.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d43e5bd4f7---18962849411.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3b46f026b---41401651141.pdfIn PDF document text
    • http://airelimpio.mx/img/editor/file/kegamap.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9ee2d60e1---xasoninavubufap.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/mirekexike.pdfIn PDF document text
    • http://k-ookuma.com/js/upload/files/sevajuwasasugagapabaxi.pdfIn PDF document text
    • https://delcinfo.ru/img/files/files/41474724477.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/beterelagexab.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/7343a37bbd6aeac9dbad46c1e281150a/nufebu.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a67f48649a5---xoboken.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607514609fde2---2950576747.pdfIn PDF document text
    • https://olterus.info/contents//files/19888182368.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160704483a7a5e---desugifaferamifogol.pdfIn PDF document text
    • http://charivne.info/images/file/82079534156.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/42929191886.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/a75d07b9d2a595b60b58b25bd2ff80fe/devutikufagigegabefereg.pdfIn PDF document text
    • https://soccerauquebec.com/userfiles/file/38118563486.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609f26f077e5c---9573467440.pdfIn PDF document text
    • http://rfamilylucas.com/clients/73238/File/wugomewatesunazikapobajus.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_off0000d12c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD12C 18112 bytes
SHA-256: fdb27f67226a47cd34205d930f5f77c393f329c2c0da59cbd1cb2890ad94b0ce
font_01_sfnt_off0001004c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1004C 10756 bytes
SHA-256: 802f28ed7b6ebb79aec61186b9c615d97da5cbe1ea80c0aed18e3794b59be582
font_02_sfnt_off00011901.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11901 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

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