Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c8642e5f5dcbac0…

MALICIOUS

PDF

69.2 KB Created: 2020-12-17 05:31:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7311114a194ce1a2886a6817dca79fd0 SHA-1: d72fcc263834886f05dd774945b387dbe3afa55c SHA-256: 4c8642e5f5dcbac0a37c5dabb2ca4a4edf7c82e82ea47649b63201e6cdaafecd
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are to benign-looking documents, but one critical heuristic identified it as a 'PDF_SEO_LINK_FARM'. The primary malicious URL, 'https://traffking.ru/strik?utm_term=firestone+high+school+yearbook', is likely used for phishing or to redirect to further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://traffking.ru/strik?utm_term=firestone+high+school+yearbook
    • https://cdn-cms.f-static.net/uploads/4450241/normal_5fa273501897a.pdf
    • https://vazujupipizake.weebly.com/uploads/1/3/4/7/134719511/tobolarire-gemexaz.pdf
    • https://cdn-cms.f-static.net/uploads/4367300/normal_5f87b6951cab0.pdf
    • https://kejemixixuroguw.weebly.com/uploads/1/3/4/5/134530022/8500029.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/881b5f6b-d209-47cf-954f-00324d21051f/gymnastics_games_free.pdf
    • https://static1.squarespace.com/static/5fc34462ab79f442f238dc9b/t/5fcab71fa400d748f5c49911/1607120671783/linking_verb_definition.pdf
    • https://uploads.strikinglycdn.com/files/ce270799-0e36-49a1-9aca-a98878356be5/j_crew_employee_handbook.pdf
    • https://uploads.strikinglycdn.com/files/ff962861-90f8-4e01-839b-48a9c4d953e1/midwest_death_notices_ireland.pdf
    • https://s3.amazonaws.com/luramamelolem/46426309303.pdf
    • https://uploads.strikinglycdn.com/files/b8715440-0ce4-409f-aef9-6fff1db225fc/62399661639.pdf
    • https://s3.amazonaws.com/jozetej/kinemaster_intro_templates.pdf
    • https://uploads.strikinglycdn.com/files/001ad198-2e44-4401-9d9a-5f409c4e637a/jutobab.pdf
    • https://s3.amazonaws.com/mixanaz/answers_to_cambridge_checkpoint_english_workbook_1.pdf
    • https://s3.amazonaws.com/samopakamefap/best_face_recognition_app_for_android.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d152.bin
49d9ee1589f566a3413e5206887be388c1adf36c1fe26ce7bb5a1339c26df9b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD152 5324 bytes
font_01_sfnt_off0000e37b.bin
b129f1597543bea3b36a795e9948beb811efc73e9e3cdcbdda63a3e8e67eaf7d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE37B 10820 bytes