Malicious PDF — malware analysis report

Static analysis result for SHA-256 25e8463d9a921662…

MALICIOUS

PDF

75.7 KB Created: 2021-03-22 07:05:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 145a72d2c81ca30292ec7c1e603b0cb5 SHA-1: 08f32dae6ad4fe22c1a82f0de3b812360ff4c955 SHA-256: 25e8463d9a921662fe6f11f8928b0f33616370ee9ada8b2b378f4c9eca96bb6c
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, containing numerous external URLs pointing to other PDF documents, some hosted on disposable domains. This suggests an attempt to manipulate search engine results or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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/award?keyword=beehive+class+9+pdf+summary PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470209/normal_6038e4aef03a3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368496/normal_602f0e062bec5.pdfIn PDF document text
    • http://anyita.space/bovefotimuff2tqh.pdfIn PDF document text
    • https://cdn.sqhk.co/tiwumixe/X2yjiio/49968766014.pdfIn PDF document text
    • http://ttop-shop.com/channel_4_news_detroit_reporterssd46o.pdfIn PDF document text
    • http://graatorama.fun/ielts_fever_general_reading_test_30_answersl2bob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374207/normal_6052db9e6b2bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458838/normal_5fdb56686ba76.pdfIn PDF document text
    • https://cdn.sqhk.co/genopeno/bmjd2JW/rotixusinovokesisa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425921/normal_603632a175218.pdfIn PDF document text
    • https://cdn.sqhk.co/zofonabiz/Mghjdgg/10686999017.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409248/normal_604fc9e69cadb.pdfIn PDF document text
    • https://cdn.sqhk.co/norowitidot/AuievFS/affordable_helicopter_rides_nyc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7f06b679-e14d-4525-8955-d56a7cf6f710.filesusr.com/ugd/79e5df_85582131d6ea4abf945e1a5449805672.pdf?index=trueIn PDF document text
    • https://1b6fbac1-9b66-4609-9151-81f5d4c316f7.filesusr.com/ugd/5e81b9_1aa3e0bc48484dcfa73d58142221da96.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vuxagixil/japan_visa_application_form_sample_with_guarantor.pdfIn PDF document text
    • https://156bb51f-0b62-477f-88ca-8620af00812b.filesusr.com/ugd/e3ff21_6f78724a00be44c99ec256f4063a4797.pdf?index=trueIn PDF document text
    • https://367e539a-c541-4439-991c-4bf2bef2aa7a.filesusr.com/ugd/77d535_74764087fbf8404d9c8cc8ef67944fbf.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dosalapasenow/template_for_wedding_envelope_printing.pdfIn PDF document text
    • https://s3.amazonaws.com/jagux/zejotulutatomiz.pdfIn PDF document text
    • https://0f7a2101-273c-4f7f-b1fd-079d1ad923c1.filesusr.com/ugd/a7ea6f_053a8e0952344d179a815faff65de281.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muwemivumazulax/37610538597.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_off0000e96e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96E 5760 bytes
SHA-256: 5e98790822e04eee632b8d87a202a09c55897143ffb2d24353467ca3af5e32b2
font_01_sfnt_off0000fcee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEE 10580 bytes
SHA-256: 6ad13d2948ae26e7bfda803421d8e6d5bebb1d1cf8ab15cb0698dcba06e5cac0