Malicious PDF — malware analysis report

Static analysis result for SHA-256 7371eabb77dab5b8…

MALICIOUS

PDF

81.5 KB Created: 2021-03-31 10:54:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 6ef18fb2624d81f9024ce50acf1a049f SHA-1: c164f7a122c5d76dc1221564aef4718735fe8da6 SHA-256: 7371eabb77dab5b81bd2b1ac7fdb552a431a65e24496be048aabfe43ec735504
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs, with one pointing to 'bologen.ru', suggesting a lure to download a payload disguised as a university prospectus. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further indicates a malicious intent to distribute files via a network of disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bologen.ru/award?keyword=university+of+cape+town+prospectus+2020+pdf+download PDF link annotation
    • http://esportzmlevent.com/how_to_set_infrared_thermometer_to_fahrenheitr3klx.pdfIn PDF document text
    • http://peteferix.mypressonline.com/how_many_decibels_is_a_dishwasher.pdfIn PDF document text
    • http://sikudej.22web.org/electrocardiograma_guyton.pdfIn PDF document text
    • http://sidawiw.iblogger.org/midodrine_davis_drug.pdfIn PDF document text
    • http://kmplitka.shop/864295263320yoxq.pdfIn PDF document text
    • http://warokibujiz.getenjoyment.net/the_fortune_at_the_bottom_of_the_pyramid_prahalad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384820/normal_5fd309738111b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447086/normal_60588221f1e15.pdfIn PDF document text
    • http://tobubolixej.iblogger.org/93661144971.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416125/normal_6033886188619.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419430/normal_5ff304c6b8b1f.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/feliso/91501443087.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd8781d5-cd21-404d-acca-20d13b7ca8c6/6687548254.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b4d0f77-876b-4238-8710-d960ba7af8dc/what_time_does_stock_market_open_and_close_in_california.pdfIn PDF document text
    • https://s3.amazonaws.com/pewibim/pisobu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b83f10f-8725-4bc0-a0d4-090670da12d8/gozeleselonegila.pdfIn PDF document text
    • http://zukomakiduw.myartsonline.com/99388084727.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/78248552-dfe3-4d59-b89f-dd5679b96805/jajuveguxodivemosot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/145c4575-0bea-4efb-98c6-f3596af2a9f1/how_much_is_a_2011_ford_focus_worth.pdfIn PDF document text
    • http://wutorokanotomav.onlinewebshop.net/lobuporeforeki.pdfIn PDF document text
    • https://s3.amazonaws.com/pasutiz/building_construction_technology_notes.pdfIn PDF document text
    • http://pevogikuxupeja.onlinewebshop.net/aprender_sueco_portugus.pdfIn PDF document text
    • https://s3.amazonaws.com/goneduzum/tijemezima.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://scripts.sil.org/OFLIn 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_off0000e827.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE827 5668 bytes
SHA-256: dd97e4cc118dc9fbd01a3e7b7e74861ef0a9d9d19c78f5e09cec66bca2407e3c
font_01_sfnt_off0000fbaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBAA 11416 bytes
SHA-256: fa6c8c24cc504b6d82c8f6bb64381b57f9e4f9a9595e23eaf4fcd2191221b185
font_02_sfnt_off00012284.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12284 16204 bytes
SHA-256: c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449