Malicious PDF — malware analysis report

Static analysis result for SHA-256 af9f5c42ff3dbc57…

MALICIOUS

PDF

76.4 KB Created: 2021-04-07 19:51:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 43765562fe22de3f6fe41ee9d57b23c6 SHA-1: b1bf96aa5fc4ee4ea4f3363f9d12f319d182d132 SHA-256: af9f5c42ff3dbc57e0f2a46bcaf7f6315f11ad4b842312322927f575c5cb2d5e
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains heuristics indicating a social engineering lure to install a browser extension or update, a common tactic for credential theft or malware delivery. The embedded URL points to a suspicious domain, likely serving the malicious payload or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://resalured.ru/strik?utm_term=what+is+psychology+fourth+edition
    • https://cdn-cms.f-static.net/uploads/4485305/normal_605094d09545d.pdf
    • http://tarekupi.scienceontheweb.net/bsc_math_book_file.pdf
    • https://cdn-cms.f-static.net/uploads/4488317/normal_5fd30edb3d7d5.pdf
    • https://cdn.sqhk.co/buzulexoxuve/icHibFO/nugezibabilobokowufe.pdf
    • https://static.s123-cdn-static.com/uploads/4444369/normal_5ff33d80caf8c.pdf
    • https://static.s123-cdn-static.com/uploads/4389104/normal_5fed7728ea688.pdf
    • https://cdn.sqhk.co/kenalutaxi/fhhdi03/google_chrome_update_free_filehippo.pdf
    • https://cdn.sqhk.co/leporolino/QfgjHOu/kujubidepeb.pdf
    • https://cdn.sqhk.co/wekonexiw/f2geib1/vigowevomuginajokuvike.pdf
    • https://cdn-cms.f-static.net/uploads/4376602/normal_603185134b827.pdf
    • https://cdn-cms.f-static.net/uploads/4374851/normal_606cb0c3a6124.pdf
    • https://cdn-cms.f-static.net/uploads/4464078/normal_601391d953563.pdf
    • https://cdn-cms.f-static.net/uploads/4484399/normal_5fdaf3a482578.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/1432ca83-1109-4e01-b2d2-f5857c1f9af4/nifok.pdf
    • https://uploads.strikinglycdn.com/files/d0e50f5a-ca45-41f7-937d-b6cd02365d91/65123005217.pdf
    • https://uploads.strikinglycdn.com/files/7b87b8a0-3cd5-4631-b85e-1d8d507be222/mubogo.pdf
    • https://uploads.strikinglycdn.com/files/03d4c04d-0d88-4e34-91a7-079eacb715c6/windows_10_home_to_pro_upgrade_free_2020.pdf
    • https://uploads.strikinglycdn.com/files/5af582ae-a38a-4e48-9c9b-3db467ddf53a/99035700713.pdf
    • https://uploads.strikinglycdn.com/files/819b9189-1b18-4ce2-a9eb-e34d8895bcde/96564232639.pdf
    • https://uploads.strikinglycdn.com/files/307ff9d2-6752-476c-8732-d3a81b924edc/para_q_sirve_la_moringa_con_limon.pdf
    • http://fojosotum.myartsonline.com/31941004860.pdf
    • https://uploads.strikinglycdn.com/files/2e511ac2-8d88-4553-a3c8-3fbc38dead9f/how_to_cook_a_pork_roast_in_a_power_pressure_cooker_xl.pdf
    • https://uploads.strikinglycdn.com/files/2dc6f568-f9f0-478a-b9e3-0f4cba4a0cda/how_to_think_positive_thoughts_in_a_relationship.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_off0000ed15.bin
ce06e6a5f699270c2c9398b31bd38f82bb872ff6d73e64533506e7ab3274ab0e
pdf-font-stream PDF embedded font (sfnt) at offset 0xED15 5532 bytes
font_01_sfnt_off0000fff6.bin
1c114477cfda7613e5d9595fe4f304bd8f5613f2499ba5223d19c4085f3ff5e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF6 10588 bytes