Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bfb0438cd81a2a…

MALICIOUS

PDF

89.6 KB Created: 2021-04-17 04:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 0550f72d559f9e6499ad99088d3176f7 SHA-1: df463deb18120d836383e4012bbcb17a3f5582b2 SHA-256: 28bfb0438cd81a2a2442b1e5f1a6d5fa1ca39ab174d5a1062d6c049e7d998fca
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://maypoin.ru/strik?utm_term=ne+patriots+2015+schedule PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4488555/normal_5fffb1bf528ab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413987/normal_603402fb7f062.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455381/normal_606606fd43d4b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501791/normal_60201481e2858.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444386/normal_6042f5e244dd8.pdfIn PDF document text
    • http://verifiedbadge-lnstagram.com/how_to_use_dvr_on_dish3o6aw.pdfIn PDF document text
    • http://kimisorunutom.medianewsonline.com/sandesh_epaper_surat_today.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460446/normal_603b50f5a882f.pdfIn PDF document text
    • http://xorabawik.medianewsonline.com/mimikelowajuretu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457881/normal_5fced4e544233.pdfIn PDF document text
    • http://valuburikodajad.medianewsonline.com/caryl_churchill_cloud_nine.pdfIn PDF document text
    • http://lbaranaydin.com/the_new_bottoming_book_espaolbft2u.pdfIn PDF document text
    • http://zebrait.fun/788396821665wzje.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://7fd92c66-d3af-485c-b7a9-31529ddfb1b5.filesusr.com/ugd/997d0f_029afc80e50b4a30a7803b7a29423242.pdf?index=trueIn PDF document text
    • https://f85e9a30-dbb9-40fd-a66d-53bd7daafe07.filesusr.com/ugd/1b9faa_7999ab95596d499c8b304a640dba3f2b.pdf?index=trueIn PDF document text
    • https://994180ce-385f-4272-9833-4a204a825e0f.filesusr.com/ugd/ec0c41_f838df6c1c25429d9348a0d341cc1abe.pdf?index=trueIn PDF document text
    • https://2e03c77f-99cc-4591-9807-54d8d49c9ce6.filesusr.com/ugd/759733_5834d3963f3b4bb9a1f4ffe31d40971d.pdf?index=trueIn PDF document text
    • https://3d73ec66-e24e-4607-99a5-aa3c333c10ea.filesusr.com/ugd/a96454_0307d4d13fae406691b3108b6b6f6aa0.pdf?index=trueIn PDF document text
    • https://39472683-7d43-4bc3-882b-0947a83fd973.filesusr.com/ugd/544c7e_7ecb1623b76b45b8aba307e3b1fdebeb.pdf?index=trueIn PDF document text
    • https://fe92b815-f0fe-4223-924b-659339f44b90.filesusr.com/ugd/8f64fc_0a240937bdaa4bdc86c1efbe61977493.pdf?index=trueIn PDF document text
    • https://d54d55f4-8004-4613-9f19-7b96cbed0ae7.filesusr.com/ugd/ce4b32_eab609acf8924fdfb382128c59743d91.pdf?index=trueIn PDF document text
    • http://nabafutig.myartsonline.com/79042155046.pdfIn PDF document text
    • https://6d8b2927-5c4d-40df-b593-c6bd35e19528.filesusr.com/ugd/1adac8_e5554575f01145c0ba2660ab2734fc45.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BE 5356 bytes
SHA-256: f1fee7a7a0e6aae4c35a0491a9aceeb1387b986afb2a2a15f4f53d664cf7b04b
font_01_sfnt_off0001070d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1070D 11632 bytes
SHA-256: acc7ea7d1be3d4fe6834e84fc8011c2bdd5816963d11fa0d71fe87d7d19abe3b
font_02_sfnt_off00012eec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EEC 18104 bytes
SHA-256: a7ada0c84ca64b42caca666620f9dc821c7515ac26d2ccd5cf2c56630b097e6d
font_03_sfnt_off00014a80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A80 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3