Malicious PDF — malware analysis report

Static analysis result for SHA-256 f838a1edc1563429…

MALICIOUS

PDF

88.7 KB Created: 2021-04-01 21:20:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 8a7dfe69c02aee7fa35f2982bc6ee65b SHA-1: cdd1072ac47c533df930abc9f4dd92045a78c67a SHA-256: f838a1edc156342992b3c94415455668738dc5b588b94c52437c307ffaf9cd1d
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 hosted on disposable domains, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO abuse. While no scripts were extracted, the structure and URL patterns point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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/wix?keyword=velocity+and+acceleration+worksheet+doc PDF link annotation
    • https://nirotagikul.weebly.com/uploads/1/3/5/9/135992947/1356803.pdfIn PDF document text
    • https://limotesatax.weebly.com/uploads/1/3/1/8/131871768/kavejirepijiki_jurudu.pdfIn PDF document text
    • http://xazonem.22web.org/music_movement_and_drama_activities_for_babies.pdfIn PDF document text
    • http://dimopun.mywebcommunity.org/fopilufojojafapemam.pdfIn PDF document text
    • https://mogatuzutixu.weebly.com/uploads/1/3/4/6/134684840/mekap.pdfIn PDF document text
    • https://zeloruzo.weebly.com/uploads/1/3/5/3/135349371/3911808.pdfIn PDF document text
    • http://vagijuderotogur.22web.org/rental_agreement_form_free.pdfIn PDF document text
    • https://rewemekekebaz.weebly.com/uploads/1/3/1/4/131406535/rerowazan-pabok-luxutulemonu-zafaxiwedi.pdfIn PDF document text
    • https://ratesikumetu.weebly.com/uploads/1/3/1/1/131163578/wutorujigomebiromure.pdfIn PDF document text
    • http://wodekenizowa.getenjoyment.net/vebakopuwojuwovifaneninid.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://c7fb3737-a2fb-4e06-b71d-f78b648bb0a4.filesusr.com/ugd/a9248e_ed3a81532c1246e897635ebac9858337.pdf?index=trueIn PDF document text
    • https://0ca3454e-05ac-49fc-8d00-644b1af7be3c.filesusr.com/ugd/8bf3fc_ac3e4c0d8e7f4c618b1aa373c83ff617.pdf?index=trueIn PDF document text
    • https://c7fb3737-a2fb-4e06-b71d-f78b648bb0a4.filesusr.com/ugd/a9248e_cc57b884750c4de08998e600ff6c44c1.pdf?index=trueIn PDF document text
    • http://favagapararo.epizy.com/pdf_to_word_free_online_converter_download.pdfIn PDF document text
    • http://wojibikifi.myartsonline.com/25938974043.pdfIn PDF document text
    • https://78ee58ad-4251-4cb6-9d9e-6f806931ac90.filesusr.com/ugd/b6b4e8_26f359d4aba2461588018bbe30226944.pdf?index=trueIn PDF document text
    • https://200ee3fc-349d-4871-b5c3-2c1c69b60476.filesusr.com/ugd/7b00a0_db3ec18a5e904429bf352628562a65c5.pdf?index=trueIn PDF document text
    • https://46fb9a51-9e16-4ad8-811e-2f7ed01702f7.filesusr.com/ugd/53363c_b30d64e46491435581dcc29b6c41d3ad.pdf?index=trueIn PDF document text
    • http://rojanesifilagu.myartsonline.com/bosch_nexxt_500_series_washer_disassembly.pdfIn PDF document text
    • https://3dcfbd4a-ef33-49dc-a04a-0aaf5307c30d.filesusr.com/ugd/b47706_d324581c18fd4404ad3ef07a7f46eda3.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001019b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019B 5252 bytes
SHA-256: 1f354f47175d76acb1b07ccb6dd43b0981ad2d9308ac0043f8774a63a19ccfa9
font_01_sfnt_off0001138d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1138D 14436 bytes
SHA-256: d8ecdd3738439a2281c30244832fc32b2f25564d71fb57ee3369cebf6743fd8f
font_02_sfnt_off00013ef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EF5 16028 bytes
SHA-256: 0bae8649ba252bcfab81cb8324cfe1737d73e47191b507e117e6d0858e0066a8