Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d028432f8795f2b…

MALICIOUS

PDF

86.5 KB Created: 2021-05-20 19:55:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9d1dba51e280c55edf54300378bc6ed9 SHA-1: 8279a56187187576a5991785f72843be9a476523 SHA-256: 8d028432f8795f2bdba9c3c9b1f6d96889191dbcd4ee9f1b404ae919ca25d1cd
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a critical heuristic identifying a 'PDF_SEO_LINK_FARM'. One of the primary URLs, 'https://nipisod.ru/strik?utm_term=sample+of+short+biography+about+myself+pdf', is flagged as unknown reputation and is likely part of a phishing or malware distribution scheme. ClamAV detection as 'Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0' further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nipisod.ru/strik?utm_term=sample+of+short+biography+about+myself+pdf
    • https://cdn-cms.f-static.net/uploads/4468530/normal_60226abfe412b.pdf
    • https://cdn-cms.f-static.net/uploads/4458124/normal_6064e935d9911.pdf
    • https://static.s123-cdn-static.com/uploads/4378405/normal_5fe20ee8a50bf.pdf
    • https://fukituxepuronip.weebly.com/uploads/1/3/4/6/134605821/worino.pdf
    • https://fofirajajamide.weebly.com/uploads/1/3/4/6/134643930/jutudaxiregagukum.pdf
    • https://josaboduzez.weebly.com/uploads/1/3/1/6/131637311/monaxinoto.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/72935f6f-7fc0-4b85-a560-fcfa7aac88ec/49532851628.pdf
    • https://s3.amazonaws.com/pevarijidasalop/free_apps_jailbreak_ios_11.pdf
    • https://s3.amazonaws.com/zagapaxa/69551742183.pdf
    • https://uploads.strikinglycdn.com/files/ccc31aab-8acf-40c4-924a-7a760b0cdabb/how_long_does_it_take_to_get_a_foster_placement.pdf
    • https://uploads.strikinglycdn.com/files/3370bfeb-5022-4a37-9d2e-71d2c3ca0211/average_salary_for_lead_teller_operations_specialist.pdf
    • https://s3.amazonaws.com/wakuzidi/6788523083.pdf
    • https://s3.amazonaws.com/vonusirukete/butterball_electric_turkey_fryer_basket.pdf
    • https://s3.amazonaws.com/vovuzize/2nd_line_mod_apk.pdf
    • https://s3.amazonaws.com/pusixa/tudexubanesofiwopasuw.pdf
    • https://uploads.strikinglycdn.com/files/c4ade0b6-d884-4ba9-a2ff-55c66bcabd8b/53019587448.pdf
    • https://s3.amazonaws.com/fasudikek/maersk_aptitude_test_questions.pdf
    • https://uploads.strikinglycdn.com/files/d6d5c128-67ec-45e9-b2dc-d37b305d8241/93605132778.pdf
    • https://s3.amazonaws.com/jenagubadopi/how_to_install_water_filter_on_keurig_duo.pdf
    • https://uploads.strikinglycdn.com/files/aa602385-241d-477a-8590-0102f381a562/control_systems_engineer_salary_australia.pdf
    • https://s3.amazonaws.com/zagapaxa/free_html_admin_dashboard_template.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_off0001131f.bin
6becf7895a6996119dae49142e267bd5ea19ee2c2b3adec888f9e6f3d4d05577
pdf-font-stream PDF embedded font (sfnt) at offset 0x1131F 5800 bytes
font_01_sfnt_off000126b5.bin
9d3362528654be53c35eb246de86c1e7dfc8dccff39d6f4b0c845f100ed92720
pdf-font-stream PDF embedded font (sfnt) at offset 0x126B5 11112 bytes