Malicious PDF — malware analysis report

Static analysis result for SHA-256 de94cb65dcf7e68d…

MALICIOUS

PDF

72.5 KB Created: 2021-03-17 05:39:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 5e86b7bb4d431159d6ff311e4d97e8c4 SHA-1: 6cb45533e570dabeb1c8498a51dbfb18cd12ec31 SHA-256: de94cb65dcf7e68d8e8e2c23c54b9e7cc1805e2dd750fd46e8b636f980be638e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the presence of metadata related to 'wkhtmltopdf'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://jacksth.ru/wix?keyword=pegatron+m2n78-la+violet6+manual PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4455197/normal_5fe336bc69e6d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499979/normal_5fd1b56f83c4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445866/normal_60296c15614d0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386613/normal_6000cc0680aaa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cf4de027-7369-46c2-bf93-d69cabef2b5e.filesusr.com/ugd/868b90_479f36574514443ab32baeaa07bdb153.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jexijer/29290668214.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af053588-50fc-4879-be5b-501a07923e63/james_barrat_our_final_invention_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ab98a96-d1be-45fb-97a2-1b2bde4639fd/zosamuligur.pdfIn PDF document text
    • https://19527f6f-7821-4b33-8e58-d909ab9a203f.filesusr.com/ugd/b18fc6_6598843720314f75990546b6e2682111.pdf?index=trueIn PDF document text
    • https://1347de4c-4e54-429a-b84c-372e60bc5a2b.filesusr.com/ugd/6c98bc_cd58e1d82f7f4c8ebe19f1fca55b36be.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/46dfe696-6df5-473e-bda0-28c343114145/ap_calculus_ab_2017_multiple_choice_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a567836-fd33-4c19-865a-75848ae0e2e4/the_art_of_acting_quotes.pdfIn PDF document text
    • https://b3a1a1c9-4f8f-4fb8-b7cc-7339030cc889.filesusr.com/ugd/162fe6_5b0970e3f6bc4e00bdac9f31d9d35af1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5cec90d-3777-4738-870d-80bd356b1502/gre_practice_test_sample_questions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/120e3442-9509-4eea-8295-8710da7775c3/new_stephen_king_series_streaming.pdfIn PDF document text
    • https://s3.amazonaws.com/jivagajamav/deforestation_news_report.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/150d0cf1-4d28-49a8-b684-418743803fee/ley_de_puerto_rico_carta_de_derechos_y_responsabilidades_del_paciente.pdfIn PDF document text
    • https://60659a61-a27b-47ea-8eac-a81775c62269.filesusr.com/ugd/7a7fb1_64b1d110d4ca496dae8daf6645dd56ad.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jotizifime/between_catastrophism_and_uniformitarianism.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c160624-cc8a-45bc-b107-ab2a2ff401dd/vutawowesadutuwewem.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea5ad3fb-4380-4f23-93f9-f5bdda9f7eac/69248675988.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/617ed398-451e-4cc0-9617-4d87fd7f74e7/how_do_i_love_thee_sonnet_43_theme.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_off0000dc55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC55 5480 bytes
SHA-256: b4a1b4815b3dca57868f88fb1775ea7d3dca977a9ba78f165022e92a077baa4c
font_01_sfnt_off0000eef7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF7 11024 bytes
SHA-256: e1781dd8cf911fb4bc78941c7952e6aca402b8376e63faab1dd8a4ed67ad342d