Malicious PDF — malware analysis report

Static analysis result for SHA-256 4952eb6ec92dc4e1…

MALICIOUS

PDF

78.5 KB Created: 2021-09-12 11:21:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 92e246a2484af4a4ccd028ec79cca56a SHA-1: ac25398a47de75526bedc2c6f9d02f191324b4cc SHA-256: 4952eb6ec92dc4e1b8cfc60aa426ccc942cba96769e83d3b6888de98725f3fae
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. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to PDF files on various domains. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection, hence T1059.007 is included. The primary attack pattern is likely to trick users into downloading further malicious content or phishing for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 http://upakuika.com/img/file/32352318694.pdf In PDF document text
    • http://jobsandhi.com/uploaded_files/userfiles/files/lidogotazo.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/71267909805.pdfIn PDF document text
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/vibaweganarivaziw.pdfIn PDF document text
    • https://path.mn/userfiles/files/wipujegepufuk.pdfIn PDF document text
    • http://www.globalnautique.nl/upload/files/vaburakuba.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/82003917430.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/85107531488.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/94295253765.pdfIn PDF document text
    • http://alconsprom.ru/ckfinder/userfiles/files/pagikafifitifadimezurego.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/sakujobawidew.pdfIn PDF document text
    • http://turnyras.lt/Files/file/67504364811.pdfIn PDF document text
    • http://tyros-club.de/userfiles/file/sidegitepe.pdfIn PDF document text
    • http://ottomaniantextile.com/userfiles/file/60116436536.pdfIn PDF document text
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zodazugosozorikawigabalu.pdfIn PDF document text
    • http://parfumland.sk/upl/81167729744.pdfIn PDF document text
    • https://floridagreatescape.com/media/file/54921852871.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/c7n92nd4riq5bjpooq3tug50hj/bedewogurow.pdfIn PDF document text
    • http://aguito.madteam.net/ckfinder/userfiles/files/doreserizuduwu.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/rubor.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/161309df96d02c---momiguzomewoxijav.pdfIn PDF document text
    • http://platypusspot.org/uploads/ckfinder/userfiles/files/26334193181.pdfIn PDF document text
    • https://optimuselearningschool.aels.edu/learning/site/images/uploadfiles/daravuwolawanol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=android+sync+driversPDF 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_off0000d39e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD39E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ebb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB0 16312 bytes
SHA-256: b040d6be803337e7cf4c3413f51dc2ac45716c02284c87a4c83ea45d54b1d4b4
font_02_sfnt_off000115d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D6 10216 bytes
SHA-256: 78a01a90b76d40f995351edc58a6f510588eaf00896dd5d54244baee35ddeec1