Malicious PDF — malware analysis report

Static analysis result for SHA-256 4121afd6806f832a…

MALICIOUS

PDF

71.4 KB Created: 2021-06-02 11:55:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 149ae662c54e0ff8c5ce885c1edd999e SHA-1: afa3575fef4476dc4127315da67049319a1a3fb5 SHA-256: 4121afd6806f832aeec179b4e3337e3591e4002209e8420fd5c1282e02fa3bcd
166 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many of which point to disposable hosting, suggesting a link farm designed to direct users to malicious sites. The heuristic 'SE_MFA_LURE' indicates the document is likely a lure for credential phishing, specifically targeting multi-factor authentication or one-time codes. The primary URL identified, 'https://nomylo.ru/pbw?utm_term=how+to+fill+iosh+risk+assessment+form', is likely the destination for this phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://nomylo.ru/pbw?utm_term=how+to+fill+iosh+risk+assessment+form PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4385230/normal_60663f475ddd9.pdfIn PDF document text
    • https://xawoveramexu.weebly.com/uploads/1/3/4/0/134095940/a04867757b03.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458833/normal_60463aab428c1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426695/normal_60036dfe1d966.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4376849/normal_600090d05c762.pdfIn PDF document text
    • https://vizazoxo.weebly.com/uploads/1/3/4/6/134600102/vakilumudifa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366397/normal_5fd26c5f6fb3b.pdfIn PDF document text
    • https://kojusano.weebly.com/uploads/1/3/4/8/134872417/litibas.pdfIn PDF document text
    • https://didosetugub.weebly.com/uploads/1/3/1/6/131606008/537bfc8d04acc8e.pdfIn PDF document text
    • https://fefajuvojamunuj.weebly.com/uploads/1/3/4/7/134750085/1051859.pdfIn PDF document text
    • https://koxalisibigemig.weebly.com/uploads/1/3/4/8/134854932/rorujuwirupi-dipefozozafab-vegovifaka-fatet.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/1a39e0cb-a6e7-4753-a267-5b63cec97df9/roy_the_rat_and_his_six_thinking_hats.pdfIn PDF document text
    • http://vawaguzidatu.pbworks.com/f/15135011296.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c978c06-3fd7-48d1-ad55-4078c0228030/star_wars_saga_rpg_character_sheet_fillable.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1e96396-c791-49a4-9b8a-9e6b422e5af6/daily_writing_exercises.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a0affdb-1f2b-467f-8135-477e71e1eedc/librecad_import_dwg_file.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c9c03a7-1e02-4d3c-a8a1-1501d1b4afd4/53340171540.pdfIn PDF document text
    • http://jizakatum.pbworks.com/f/25927202334.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0cad2c57-156b-4d6c-bd20-ae4c9ef77b3d/jarakexojobofuf.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_off0000dccb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCCB 5124 bytes
SHA-256: ff47f058c5b1b9534918dee7c8ca27e566ce37bed52d90bc72d68cf599263248
font_01_sfnt_off0000ee1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1A 9956 bytes
SHA-256: 2aacee022527a268bdb5ed09dcdfe5db163c06019af064ec0fbe1fa523182219