Malicious PDF — malware analysis report

Static analysis result for SHA-256 3728cd6b08f8c8c8…

MALICIOUS

PDF

69.6 KB Created: 2021-03-21 23:16:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 2ff8fb58642a06c867e0cacf09e78b22 SHA-1: 585058bc8ce403820451e3a3c718f6a1fba74dbc SHA-256: 3728cd6b08f8c8c86079c72ea43c6a669e10efb0ab4ba4ed6a116c8dceeb77b8
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs, with one prominent URL being https://baarspo.ru/123?utm_term=vertical+milling+machine+manual. The presence of many external links on disposable hosting suggests a phishing or malware distribution scheme, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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 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.
  • 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://baarspo.ru/123?utm_term=vertical+milling+machine+manual PDF link annotation
    • https://cdn.sqhk.co/wobuwozavenu/ibeqhhE/joxazesirebilasijakasavu.pdfIn PDF document text
    • https://cdn.sqhk.co/kafosine/Agjmxjc/android_automation_testing_tools_free.pdfIn PDF document text
    • https://cdn.sqhk.co/bepasasa/jchhahb/the_cartoonz_crew_video_song.pdfIn PDF document text
    • https://cdn.sqhk.co/tajiwikiter/Lf0lCja/wordbrain_2_movies_level_1_answers.pdfIn PDF document text
    • https://cdn.sqhk.co/serodozire/gkpB8ha/free_heart_rate_app_for_iphone_6.pdfIn PDF document text
    • https://cdn.sqhk.co/gilubibawi/gqgifhe/alchemist_meaning_in_marathi.pdfIn PDF document text
    • https://cdn.sqhk.co/gawagunikuw/8QuTBuD/war_world_tank_2_unlimited_money.pdfIn PDF document text
    • https://cdn.sqhk.co/rejiwosujupa/wNBhbjh/66974483146.pdfIn PDF document text
    • https://cdn.sqhk.co/bitajububida/hGVGuhg/kipebavunipibewigokaze.pdfIn PDF document text
    • http://gasurorir.sportsontheweb.net/dd_5th_edition_character_sheet_generator.pdfIn PDF document text
    • http://xevusezes.medianewsonline.com/aerobic_bioreactor.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/40bdd5e7-d4bb-475e-b192-ae9f75c18035/dumogimorotubugutujebumon.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2267d6b0-584f-4084-84fa-0cd7ffc5e0ba/39336294502.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f1552d6e-7236-4272-9702-b23d45b1f256/922241101.pdfIn PDF document text
    • https://s3.amazonaws.com/zidenigad/mojakaladetepava.pdfIn PDF document text
    • https://s3.amazonaws.com/fedure/new_dance_dj_song_2018.pdfIn PDF document text
    • http://lupixopuvir.onlinewebshop.net/kamujatejavexu.pdfIn PDF document text
    • https://s3.amazonaws.com/zafirawit/rafosafu.pdfIn PDF document text
    • http://keregimuw.onlinewebshop.net/mama_do_you_love_me_summary.pdfIn PDF document text
    • https://c1cb471f-fc5c-4ef2-b3e1-4d0d0d09d135.filesusr.com/ugd/cc5b41_f68d410cd4aa4a40bcade2b80530b97c.pdf?index=trueIn PDF document text
    • https://97b366c7-6e8f-479a-b18e-582a09c04a3e.filesusr.com/ugd/78c764_f3777aad96fc48fcb1d52daf34056b90.pdf?index=trueIn 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_off0000d3a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A3 5000 bytes
SHA-256: f9ee663494598c2724314f31cf51381d3478de166400f924aa69fd3631956a0f
font_01_sfnt_off0000e47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47B 10608 bytes
SHA-256: 9b2b02175d6d4b3683e1e9142718c1eea90c5dd8d1268408c3f9d8dbfe72a23b