Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d499ff090a122d5…

MALICIOUS

PDF

86.8 KB Created: 2021-09-24 01:58:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2ca452f36f5811f02a6d6865b9c43c8f SHA-1: 82757124310a613d5b7f5dfcc989a66dd42aa4c3 SHA-256: 8d499ff090a122d5637f4df7c59ea48aa212259a3a3f90eeeb8867ceab96fcab
126 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, with specific heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, despite some being marked benign, point to a pattern of directing users to potentially harmful external sites. The document body is unreadable, but the heuristics strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/72449742040.pdf In PDF document text
    • http://lamexmarket.com/uploads/files/jexugokirixux.pdfIn PDF document text
    • https://laetitiabernard.fr/images/file/jutarajovaboxidupamavuf.pdfIn PDF document text
    • https://refakatci.net/userfiles/file/vamuzezifalapemubodom.pdfIn PDF document text
    • http://nenayu.com/filespath/files/20210914063624.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/61da5e5ae6933815fc546c99b111b733/23320675908.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/18867803563.pdfIn PDF document text
    • http://salespate.com/userfiles/file/12859339044.pdfIn PDF document text
    • http://quangcongluc.com/upload/files/39973735226.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/subuwanogawed.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/73470736412.pdfIn PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/30383826136.pdfIn PDF document text
    • https://spyboarcams.com/files/tudetipuxemololenesog.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/35597640208.pdfIn PDF document text
    • http://xn--d1achljw0b.xn--p1ai/content/upload/sajaxofevelisaji.pdfIn PDF document text
    • http://strandedtattoo.net/file/mutowire.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/39294331291.pdfIn PDF document text
    • https://unitytradefze.com/ckfinder/userfiles/files/91616286840.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/fupubem.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/j1gmqu6ui31jn6apmhvc00r5nr/vikadibowejapitav.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/telapirividiredomi.pdfIn PDF document text
    • http://criollo-cocoa.com/userfiles/file/vaxegavexirego.pdfIn PDF document text
    • http://etenindex.nl/images/uploads/1363261825.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/voviwikogava.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=hero+academy+androidPDF 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_off0000ea1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA1B 19724 bytes
SHA-256: 012ae5ed982f20dfa8f8875750b075e2b0761147729e1d7343d2e2a7df732de1
font_01_sfnt_off00011e2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E2A 10324 bytes
SHA-256: 658d5eb094a16e47935881811bc1635fc0b3670a3195c927bdcda43bff623bce
font_02_sfnt_off0001355a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1355A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1