Malicious PDF — malware analysis report

Static analysis result for SHA-256 c66389792a337a8b…

MALICIOUS

PDF

82.4 KB Created: 2021-04-01 05:46:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 5ece44f689de939739742956158db578 SHA-1: c449e667cc46dc3c817073eaf62bee09defa2769 SHA-256: c66389792a337a8b2f02cd81b881e2f757d5423896e3b0fc7feab22509087edd
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains or link farms, indicating a phishing or content-distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure itself is designed to lure users to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=fam+tv+show+episode+guide PDF link annotation
    • https://cdn.sqhk.co/derilunadine/wtif1Q3/free_bingo_win_real_cash_no_deposit_required.pdfIn PDF document text
    • http://deladinabixek.sportsontheweb.net/reproduo_angiospermas.pdfIn PDF document text
    • https://cdn.sqhk.co/lewiwifo/k3gSnkn/collingwood_school_wallington_ofsted_report.pdfIn PDF document text
    • https://cdn.sqhk.co/suxujaba/ijhdH1h/mibijisosofepifenirifi.pdfIn PDF document text
    • https://cdn.sqhk.co/sijiposago/ggchijy/22217128526.pdfIn PDF document text
    • https://cdn.sqhk.co/sujubowip/BCehbYg/22754983975.pdfIn PDF document text
    • https://cdn.sqhk.co/moradivovep/ahgjgOd/49760504031.pdfIn PDF document text
    • https://cdn.sqhk.co/posukomokufi/gewn0jg/brain_games_for_dogs_on_crate_rest.pdfIn PDF document text
    • https://cdn.sqhk.co/letarezetap/iihhef5/96373328558.pdfIn PDF document text
    • http://niludop.22web.org/blaise_cendrars.pdfIn PDF document text
    • https://cdn.sqhk.co/xegunorasu/ihggf0h/37042444777.pdfIn PDF document text
    • http://sumigemag.mywebcommunity.org/90329780399.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d429d46a-6203-486b-8c9d-ede5597e1383.filesusr.com/ugd/419b00_1cf945090f0a4cd4ac0333c706e7bfe4.pdf?index=trueIn PDF document text
    • http://vifabor.rf.gd/52055913916.pdfIn PDF document text
    • https://s3.amazonaws.com/juvetaso/what_ink_does_hp_4500.pdfIn PDF document text
    • https://3c8197b3-f999-4f29-b3da-fbdfea3dbf34.filesusr.com/ugd/0047a4_6c737872f4cb4e40b1512bf1c5a53945.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/juvosi/81699896195.pdfIn PDF document text
    • http://jasunusemoki.onlinewebshop.net/95364297399.pdfIn PDF document text
    • https://s3.amazonaws.com/bevekizadoxuj/from_now_on_drum_sheet_music.pdfIn PDF document text
    • https://f59c0a4d-c104-43ac-8966-a5978cdf1b8c.filesusr.com/ugd/0c1ebd_c411bfe7c7bc46a6bdcda56eb14e106d.pdf?index=trueIn PDF document text
    • http://lodafudamisov.epizy.com/probability_tree_diagrams_gcse.pdfIn PDF document text
    • https://29aa9d28-cc9d-45fc-8d86-3718b5881c84.filesusr.com/ugd/74c34a_537033b79bc14ed9bf3f77ac3f04b4bd.pdf?index=trueIn PDF document text
    • https://ca3ec1ac-6ff7-4c8f-ae0f-86a30d86e335.filesusr.com/ugd/3615fb_1059c0bdadcb4b6bb1de57ba42ede9e6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/buxoparadazegu/chief_information_security_officer_roles.pdfIn PDF document text
    • http://widifusi.myartsonline.com/blood_collection_tubes_color_code.pdfIn PDF document text
    • https://s3.amazonaws.com/werowibovezoje/krishna_bansuri_tone.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_off0001049e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1049E 5352 bytes
SHA-256: 16ceab90aea8cd0a1670296a353aa8809f9518614e4c02681c9f2f12b9c45d9c
font_01_sfnt_off000116d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D1 11000 bytes
SHA-256: f509af725958e927332cb75994b1db8d299bdd1ab88fd2dbbf386f5d6918a0fb