Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c105ed99fe0c535…

MALICIOUS

PDF

69.3 KB Created: 2021-09-12 22:50:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b5f70ea7a3bce00b44aeab4076f4fb93 SHA-1: c5326c0b258367ff9ee2f1694e9027d51c3c45ae SHA-256: 9c105ed99fe0c535bb387b7b38559552d09629489467f966b3ee3cef6395334c
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to disposable hosting. The document body is heavily obfuscated and unreadable, suggesting it is designed to conceal its malicious intent rather than convey information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://hoanhaochemical.com/uploads/files/18824371173.pdf In PDF document text
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/fajilabudin.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210901065539.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/91593567745.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/161315df770358---19931134906.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/13820380843.pdfIn PDF document text
    • http://gjbbang.com/userData/board/file/35520439741.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/wakofijeke.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/5377094775.pdfIn PDF document text
    • http://viajaconsciente.com/imagenes/userfiles/file/gexufaxit.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/98323128506.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/161314acda66b9---61463693037.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/6857311203.pdfIn PDF document text
    • http://sdsenlex.com/upload/files/zebepa.pdfIn PDF document text
    • https://onlineadda.net/ckfinder/userfiles/files/91205188814.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2f04a897d---modavixa.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///sabiseduker.pdfIn PDF document text
    • http://softtox.pl/new/userfiles/file/baruwok.pdfIn PDF document text
    • http://speaklifeiamgreatness.com/files/files/pokemabanuvavubonibaton.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/64222466284.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/xibowanofoxada.pdfIn PDF document text
    • https://4cmedica.com/ficheiros_upload/file/mokolaxibimoxa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=pokemon+crystal+gba+romPDF 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_off0000afc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFC8 10828 bytes
SHA-256: 3c4a9ee8940d5ae35b138c40f57693ed098578e9584cbc1dfaf589b7f0a0509d
font_01_sfnt_off0000c8e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e0f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0F3 15396 bytes
SHA-256: 37e7befc7cb5dc2a683d2045a4bb9130804ee75849b48774a3a1471148200be9