Malicious PDF — malware analysis report

Static analysis result for SHA-256 975b2775ac4d1b02…

MALICIOUS

PDF

69.5 KB Created: 2021-09-27 23:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6aa73cd373492d107c0a3907a4effb2e SHA-1: 92be20086e1f4c5097cc35e215d8f9cae79a0a23 SHA-256: 975b2775ac4d1b025ed7b6a892be82e359850f95af811a0d895caf4cad2b45fd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high ML score and ClamAV detection as a phishing trojan. It contains numerous embedded URLs pointing to external sites, many of which are part of a link farm hosted on disposable domains. The document body, though obfuscated, indicates it was generated by wkhtmltopdf, a tool often used to create malicious PDFs. The presence of external URIs suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=wifi+hack+trick PDF link annotation
    • https://4wheelchile.cl/admin/uploads/file/75200998574.pdfIn PDF document text
    • https://thefencedocumentary.ca/adminfiles/file/dilobunewijiv.pdfIn PDF document text
    • http://bentleyplemtech.ru/userfiles/file/12754632622.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/58444728380.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/14648800984.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/vibepagilurajada.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613005cbc66b2---87198026178.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/nimedazabemonimofa.pdfIn PDF document text
    • https://giriconsultancy.com/content_files/files/69334930998.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/80771017455.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/63106739985.pdfIn PDF document text
    • http://senvietsystem.com/ckeditor/upload/files/3078120747.pdfIn PDF document text
    • http://medrea.ru/upload/files/niximikuzawexumodeja.pdfIn PDF document text
    • https://sportnazona.bg/f/uploads/files/tuvusologenu.pdfIn PDF document text
    • http://cssh.es/img/file/kokopovonarisamojis.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/dowatagakupal.pdfIn PDF document text
    • http://epoxidice.ro/mm/file/guwejamikirutexop.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/25535974277.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/0a23a8d57b401e69c583e9ae7a4452db/22033190023.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/zagugelirozufodojejumo.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/pomadajivudipudo.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/sogajijilelasifelupasofoj.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/53288054068.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/meduxetojudugaw.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_off0000b079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB079 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c88f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC88F 9948 bytes
SHA-256: f1905f484d45bc04306e849548a554dcc736edc144aa4d895a71509640e70f91
font_02_sfnt_off0000deae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEAE 16424 bytes
SHA-256: 59386f8c21de023f6feba0c8cb138597be58c7804ed3a8ddae61f70ccd8a8c7b