Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b94447753ad8923…

MALICIOUS

PDF

70.2 KB Created: 2021-02-27 14:54:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: bb7083232885dc1c5cc32696287373dd SHA-1: e255199c829b8314648e4a7d2e46683321cdf697 SHA-256: 5b94447753ad892339b6edf8b79f45d1ee8ab15a3b29b82b263cadb668cd5983
184 Risk Score

Malware Insights

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

The sample is a PDF document flagged by multiple heuristics as malicious, including a critical finding for linking to known malicious redirector infrastructure. The embedded links, such as 'https://dafemum.ru/wix?keyword=fe+civil+practice+problems+michael+lindeburg+pdf', are designed to direct users to potentially harmful websites. The ML classifier also strongly indicated maliciousness, supporting the overall assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/wix?keyword=fe+civil+practice+problems+michael+lindeburg+pdf In PDF document text
    • http://fanutoragozogow.sportsontheweb.net/does_amazon_own_the_rights_to_my_book.pdfIn PDF document text
    • http://juxefagag.22web.org/1129377619.pdfIn PDF document text
    • http://veselutut.mywebcommunity.org/jesuit_oath_debunked.pdfIn PDF document text
    • https://dunifavopugi.weebly.com/uploads/1/3/5/3/135312205/57fe751.pdfIn PDF document text
    • http://letnesil.xyz/31894539273b3pzm.pdfIn PDF document text
    • http://xejevojesinil.22web.org/what_is_the_importance_of_traditional_music.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://mumunetade.epizy.com/stratego_rules.pdfIn PDF document text
    • https://s3.amazonaws.com/tesasubawalozan/ansible_config_template_example.pdfIn PDF document text
    • http://rupesujutiwu.myartsonline.com/furikol.pdfIn PDF document text
    • https://s3.amazonaws.com/kujapomib/full_fitted_sheet_black.pdfIn PDF document text
    • http://kewetanetoza.atwebpages.com/how_do_you_program_a_genie_3_button_remote.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC74A 5608 bytes
SHA-256: fd297b7e631a7cc6428e38d2f20348ad425e9f842d0c6166f26435335f8b9eee
font_01_sfnt_off0000da2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA2D 10384 bytes
SHA-256: d334a1ba43ae8ae53ea0c46376dc6572b225169160b0bea5a0cc9d513675ae4c
font_02_sfnt_off0000fdaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDAF 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3