Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bec87e83385c8c9…

MALICIOUS

PDF

76.8 KB Created: 2021-03-17 19:20:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: ae5b6ab047768705119c0bf4b1be20fd SHA-1: 2b72b05b64738b4b21eb845cb400553435fabcac SHA-256: 7bec87e83385c8c93d8c8d9f9a310cc49cf828213cd48aff66d6655efdc13c4e
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 0.9997

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://crophysi.ru/wix?keyword=fishing+merit+badge+answers PDF link annotation
    • https://cdn.sqhk.co/dibitarebizu/jiKaSha/8662672465.pdfIn PDF document text
    • http://eslife.pro/mortal_engines_2_bookem8np.pdfIn PDF document text
    • https://cdn.sqhk.co/ferobisuw/c4jaidi/48314384918.pdfIn PDF document text
    • https://cdn.sqhk.co/bitaxukezor/a9mpicg/modazu.pdfIn PDF document text
    • https://cdn.sqhk.co/bapinero/icjdhiz/calculadora_de_iva_el_salvador.pdfIn PDF document text
    • https://cdn.sqhk.co/bubiwalifeda/QjfegiB/bmx_bike_track_videos.pdfIn PDF document text
    • http://youtube-subscribes.com/tesis_de_tabaquismo1ja7v.pdfIn PDF document text
    • https://cdn.sqhk.co/zutomina/jdy3Zaa/kemavexemuxenujewilipeji.pdfIn PDF document text
    • https://cdn.sqhk.co/jeporikate/8dYyiab/batman_world_s_greatest_detective_achievement.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://51fd5013-30c4-43d1-89ce-86564632a3b5.filesusr.com/ugd/9f06f8_1e732cf967b640f0abcd0502a740c931.pdf?index=trueIn PDF document text
    • https://80b1f93a-fe74-4439-a81d-34814fa7a505.filesusr.com/ugd/e56fe2_df33fb895b8f46e991f7905fb1fc3525.pdf?index=trueIn PDF document text
    • https://cd489911-dc6d-4439-b408-84622343fb93.filesusr.com/ugd/d8e941_00a829e9cb1d49acad3bd553dee05d6f.pdf?index=trueIn PDF document text
    • https://8d5bcf17-53f2-4f21-b585-7a27aef14131.filesusr.com/ugd/7baf93_b3ce75b16d034f1d9c02882440a6fa89.pdf?index=trueIn PDF document text
    • https://0cfe495c-9a5f-46a1-a5f3-fb21b6211bac.filesusr.com/ugd/7aabb2_a7fd71bc03eb4f569eed02a2dd2697ad.pdf?index=trueIn PDF document text
    • https://44dd6259-7513-41c7-b2f1-b2b1fc385d2e.filesusr.com/ugd/63022f_43a1b609fd744b0c8080138e24d67ec0.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/negonanopix/47087244325.pdfIn PDF document text
    • https://s3.amazonaws.com/luramamelolem/legal_profession_uniform_admission_rules_2015.pdfIn PDF document text
    • https://a2ae8793-a99f-480d-a3bc-849ef63d34f7.filesusr.com/ugd/cc207a_62be5025b2974ceb9b551825277e87c0.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wulagisi/where_to_buy_petsafe_invisible_fence.pdfIn PDF document text
    • https://b4140449-9b96-4148-8619-c9b3eed7b48c.filesusr.com/ugd/c33cdb_5fa0a8b1d9fb4a6aaf6ff9509c70cf99.pdf?index=trueIn PDF document text
    • https://f2f8a3c9-3ea7-4a25-b7e2-3e2749f32899.filesusr.com/ugd/f0e51d_e29d548921a5455eb1e6f24d7683cec7.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2A 5392 bytes
SHA-256: 3b758b36f013b4eebad3daa017e67d170799c4361a2c04d818b2c24339825617
font_01_sfnt_off00010166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10166 10860 bytes
SHA-256: 5908a4955f3e5610148bed108ebe7e16f357ccb339cc8a50c341c5e172a49250