Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee53e9a60285f758…

MALICIOUS

PDF

85.0 KB Created: 2021-02-24 21:47:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: ea0f6852ea6208c916e6b97e338851e2 SHA-1: 6d7ce807483a763ee12ea12e23d757f3e6c6b6b9 SHA-256: ee53e9a60285f7587b600cb18439b1c05963360dd2f430206db3e44e8b8dcc57
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with 'https://maypoin.ru/aws?utm_term=usmle+step+1+price+2021' being a prominent example. The document body, though heavily obfuscated, contains text related to 'USMLE step 1 price 2021', suggesting a lure to direct users to potentially harmful external sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the malicious nature by indicating a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://maypoin.ru/aws?utm_term=usmle+step+1+price+2021 PDF link annotation
    • http://persequen.com/79873695546ai9gu.pdfIn PDF document text
    • http://giwapozolaleg.mypressonline.com/faputet.pdfIn PDF document text
    • http://unosital.space/poor_economics_a_radical_rethinkingil8ec.pdfIn PDF document text
    • http://arnautmebel.ru/john_lennon_imagine_sheet_music3jr4g.pdfIn PDF document text
    • http://avto-document.site/mimpi_ular_sawa_kejariv8xt.pdfIn PDF document text
    • http://reabook.online/free_business_brochure_design_templateshcfal.pdfIn PDF document text
    • http://zomewegi.iblogger.org/gulibuwel.pdfIn PDF document text
    • http://kikababono.mywebcommunity.org/digital_marketing_bsc_london.pdfIn PDF document text
    • http://nakekizedexu.getenjoyment.net/a_la_recherche_du_temps_perdu_proust_commentaire.pdfIn PDF document text
    • http://tradebot.space/46175354673wa0tp.pdfIn PDF document text
    • http://nubebukexowi.66ghz.com/lekexem.pdfIn PDF document text
    • http://kogegoleteneka.iblogger.org/how_to_fundraise_with_a_restaurant.pdfIn PDF document text
    • http://gosoxegekiri.mywebcommunity.org/2nd_grade_math_assessment.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fupuzujovo.epizy.com/vudirujogejof.pdfIn PDF document text
    • http://genosumexeser.epizy.com/video_coraline_full_movie_subtitle_indonesia.pdfIn PDF document text
    • http://xivubijorudi.epizy.com/danganronpa_another_episode_guide.pdfIn PDF document text
    • http://kivozusemu.atwebpages.com/murray_lawn_tractor_for_sale.pdfIn PDF document text
    • http://ximitexus.epizy.com/school_calendar_2019_to_2020.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F07 5184 bytes
SHA-256: 47b53c8b3c2ede6757ebc289e53f763955ee28689956e4d29ed63cdf22a975a9
font_01_sfnt_off000120a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120A6 11392 bytes
SHA-256: 9fc62dd051c1dfeadc301ce531e2bd1f14eec353b1ed47382995587128f3ee7d