Malicious PDF — malware analysis report

Static analysis result for SHA-256 37ec5ce3f8c845a2…

MALICIOUS

PDF

72.1 KB Created: 2021-06-08 01:49:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 03309545cceedab865b5aabfff8ae4ec SHA-1: f2f16183036e4084b241129496ebe33c46b59807 SHA-256: 37ec5ce3f8c845a2d2679a4ae1f2c95e305e90d5df617a60d2bb63173234498a
126 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, with one specifically pointing to 'crewmak.ru' and including a 'utm_term' parameter suggesting a phishing lure related to 'hepatitis b treatment guidelines'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for multiple links, reinforcing the phishing or malware distribution intent. No scripts were extracted, but the overall structure and URL usage suggest an attempt to redirect users to malicious content.

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
  • 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://crewmak.ru/pbw?utm_term=hepatitis+b+treatment+guidelines+2018 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4422631/normal_5fe8badbde093.pdfIn PDF document text
    • https://japapitamamevoj.weebly.com/uploads/1/3/2/7/132740309/nuwufiz_redijafe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459323/normal_606d2cadecc71.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426810/normal_6009333a6f0e2.pdfIn PDF document text
    • https://moxamegok.weebly.com/uploads/1/3/3/9/133999551/4c9d6209cf3a11.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://ziludezubeju.pbworks.com/f/how_to_get_a_bikini_body_in_2_weeks.pdfIn PDF document text
    • http://poxanoralanu.pbworks.com/w/file/fetch/144426225/dakifufabalanutudu.pdfIn PDF document text
    • http://zuvevetub.pbworks.com/w/file/fetch/144422226/spoofer_pokemon_go_android_apk.pdfIn PDF document text
    • http://lipovosufuk.pbworks.com/f/how_to_remove_duplicate_entries_in_google_sheets.pdfIn PDF document text
    • http://nijominem.pbworks.com/w/file/fetch/144709839/7786061757.pdfIn PDF document text
    • http://xivoxibuza.pbworks.com/f/78362616281.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75266305-045d-402f-8621-6b945d5556a6/97722371638.pdfIn PDF document text
    • http://zanuraj.pbworks.com/f/brief_answers_to_the_big_questions_in_tamil.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7243f996-d6d0-4d74-ae9f-39a09f93b88f/lowrance_hds_7_gen2_touch_installation_manual.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_off0000d9bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BD 5900 bytes
SHA-256: b990093812430edddb583c5de090e381370b1d1fed428501350837371c66af8a
font_01_sfnt_off0000edb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB0 10836 bytes
SHA-256: cebb8716a294419adfec7ba0c4fe517f7a5197d97a8b1761dabe2a910de26e25

Open this report in the interactive analyzer, or submit your own file for analysis.