Malicious PDF — malware analysis report

Static analysis result for SHA-256 3706f1636df7bfee…

MALICIOUS

PDF

71.6 KB Created: 2021-10-01 14:47:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 24e482bd9b778270bd3d3bda43788512 SHA-1: ec77d8efbe7d98c69bb77740bf9a7e1ff5c8267a SHA-256: 3706f1636df7bfeeb5ee2d426e2331515500fb728d1c0202abc7c0f0a7109bc4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm designed to redirect users. The presence of embedded URLs and the heuristic indicating a link farm suggest the primary goal is to direct users to malicious websites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crysiq.ru/uplcv?utm_term=software+transfer+file+pc+to+android PDF link annotation
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/2b0069aae6498033625e2b2d3ba8f11d/bisujoworegexoxowime.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/30376466520.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/56077054525.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/42966610527.pdfIn PDF document text
    • http://cabini.it/userfiles/files/wekilowalozufonuwo.pdfIn PDF document text
    • http://remont-m.com/userfiles/file/19080412242.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6b41ebf2504cd51bcfaca747b72a5c1f/mopevolozasetusoja.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/xofobekelonumusajogugazi.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/fumiwut.pdfIn PDF document text
    • http://ned.ru/uploads/files/76869008724.pdfIn PDF document text
    • https://sistemagestiondpr.com/userfiles/file/16473586982.pdfIn PDF document text
    • https://granitabrasive.ro/editor_up/komesoferorivovavojupa.pdfIn PDF document text
    • https://vientangluc.com/upload/files/besejigukolulinifexivufa.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/nemiporabonuw.pdfIn PDF document text
    • http://belloverde.net/emailer/file/83051265163.pdfIn PDF document text
    • http://cdkuys.handysociality.com/upload/files/56987389839.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/69549146822.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/30226628139.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/27521129234.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/fufimegitavujimab.pdfIn PDF document text
    • https://micsys.in/userfiles/file/2149129902.pdfIn PDF document text
    • http://fundacionecla.org/resources/original/file/vuvoxipejosurujur.pdfIn PDF document text
    • https://labelmarket.eu/data/file/11499578504.pdfIn PDF document text
    • https://silky.ae/images/bulk_images/files/wutojewukujekapugejafaze.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/12363978186.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/getomozakimen.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_off0000b3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A7 10772 bytes
SHA-256: d32efaa5f9a4bc8ca79765bef40c8ec61e69820b1963309f6a1b4d3f4f33e651
font_01_sfnt_off0000cc9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC9F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e4b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B1 17120 bytes
SHA-256: eba57887a7375e4a3b0a260ed10876bc4b28378d1216f6fca21ac33116eb26ae