Malicious PDF — malware analysis report

Static analysis result for SHA-256 21cf28ae9a665761…

MALICIOUS

PDF

78.8 KB Created: 2021-04-02 18:47:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 0a823d52b8285ec608b93824162b46b1 SHA-1: 7a5122eedfa7e7b0ab3143daa7e30cb4420d358c SHA-256: 21cf28ae9a665761b19c16fe5160542e89c28f16932526058ad251f02dc5992e
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs and is flagged as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the nature of the embedded URLs and the 'link farm' heuristic point towards the use of external resources to deliver malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://soxebez.ru/award?keyword=el+diccionario+de+armando+hoyos+pdf PDF link annotation
    • http://hisgohar.site/54085186854og55v.pdfIn PDF document text
    • http://copyrightviolationcenters.com/wordpress_templates_portfolio_designentlq.pdfIn PDF document text
    • http://esportzmlevent.com/all_you_need_to_know_about_the_music_business_table_of_contentshpc7i.pdfIn PDF document text
    • http://rubka.space/an_introduction_to_language_10th_edition_fromkinstkfd.pdfIn PDF document text
    • http://instofficial.online/subupodinapibobawidwl33b.pdfIn PDF document text
    • http://winfreeiphone.xyz/lujibogobifh4jdi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418381/normal_5fe5a5869c0cb.pdfIn PDF document text
    • http://operationhomeplate.com/guess_the_pic_level_114_answersjapn3.pdfIn PDF document text
    • http://businesslinecenter.com/05_mustang_auto_to_manual_conversionx01dj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447631/normal_604e4aaa936c8.pdfIn PDF document text
    • http://about-central.com/75313527200lulb7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3a5aa097-47f9-475f-9992-83bceef25cc3.filesusr.com/ugd/f55bec_7b8521dc803241639d04d9393baccecd.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/85195737-f552-4eff-acb2-410f50dc3ef8/dagamexeluturejesamuso.pdfIn PDF document text
    • https://b1b0174c-961c-4936-87f6-765e1132391e.filesusr.com/ugd/6cf804_670e83370f28485ead23c51040b464b4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/287deef8-1263-40bc-8e8d-4a814b6eb07e/probability_notes_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d9491546-e00d-4899-9e88-7b0776101076/vakixamozobe.pdfIn PDF document text
    • https://a29d81ee-e589-4368-99bd-4e0be04eb4c0.filesusr.com/ugd/a89e6e_7941d960966c4a24aff28d386f01653a.pdf?index=trueIn PDF document text
    • https://7ae52be2-ba3c-41fb-8935-29281088223e.filesusr.com/ugd/affaa6_cac10f1701f5482b82918055f2d427ba.pdf?index=trueIn PDF document text
    • https://459ec6dd-5b69-4322-a182-74abbfaa0e48.filesusr.com/ugd/221eaa_b1d7b94812a3406a9b5475ccd3f7a01f.pdf?index=trueIn PDF document text
    • https://4ac36a2f-1533-488b-b282-cf34cdace458.filesusr.com/ugd/bcfc12_42b41daf1b93456fba84a7f97e28960e.pdf?index=trueIn PDF document text
    • https://2d66045e-c276-4037-81df-184b25840e97.filesusr.com/ugd/cdf3e3_02f5427dc7524cd2ace59a803e408931.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/22463c9f-e85e-4251-a1e1-a637b19705f7/how_to_make_a_smoothie_with_frozen_fruit_milk_and_ice_cream.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_off0000f0f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F3 5452 bytes
SHA-256: a7edd52771a71ec4aaf48883dd8f116e09b85ada3d429f7908f91c5584265dd2
font_01_sfnt_off00010361.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10361 12632 bytes
SHA-256: 9fdce57744cb0ae184cdc2db2a74b1b79088ac851a5f26909a691f218617c2ab