Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b77ca634bea0878…

MALICIOUS

PDF

68.4 KB Created: 2021-03-21 11:56:29 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 4e907908fa4676b35649d82f76086294 SHA-1: bdd1de4d2c6f5fa3b7543be55754d73473c56590 SHA-256: 8b77ca634bea0878224d1f02f8e7224f85e3726b0966d3d06390b45efe01dea4
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan', and an ML classifier indicating maliciousness. It contains numerous external URIs, many hosted on disposable domains, suggesting a link farm or phishing attempt. The document body, though heavily obfuscated, contains text related to 'geometry chapter 9 test answers', likely a lure to direct users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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 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=geometry+chapter+9+test+answers PDF link annotation
    • https://romevezijije.weebly.com/uploads/1/3/4/7/134756673/999134.pdfIn PDF document text
    • https://bakadowo.weebly.com/uploads/1/3/1/3/131380427/ziloz-vimenovusozos.pdfIn PDF document text
    • http://ighelpcenter.xyz/tuwufofoporb3ywe.pdfIn PDF document text
    • http://rikafitamedad.medianewsonline.com/martin_luther_king_last_speech.pdfIn PDF document text
    • http://xepidenad.scienceontheweb.net/pipixaxiworusugegorasavuj.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401976/normal_5ff5766570aed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408582/normal_60546a7391374.pdfIn PDF document text
    • http://domen3.club/xoxazovaravofiwikuvageptpnrw.pdfIn PDF document text
    • http://pakirekugep.scienceontheweb.net/pidup.pdfIn PDF document text
    • http://vomuniwawan.iblogger.org/fokamonefubidugokakaxupuk.pdfIn PDF document text
    • http://usejus.pro/zupajulan70hlt.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446782/normal_6056687e1b759.pdfIn PDF document text
    • http://fubikopelemom.mypressonline.com/can_i_replace_my_optimum_modem.pdfIn PDF document text
    • https://wojawodexof.weebly.com/uploads/1/3/4/6/134673733/7632503.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416938/normal_6054acb5f3370.pdfIn PDF document text
    • https://rumodabumuxe.weebly.com/uploads/1/3/1/8/131857513/6134213.pdfIn PDF document text
    • https://dupujemewo.weebly.com/uploads/1/3/4/0/134040979/eab1d.pdfIn PDF document text
    • http://mimudobaros.22web.org/narasimha_karumanchi_data_structures_in_python.pdfIn PDF document text
    • http://hamlikjorettoop.ru/delonghi_air_conditioner_error_codes_e6d34ob.pdfIn PDF document text
    • http://porizaritofo.mypressonline.com/active_and_passive_voice_formula_for_all_tenses.pdfIn PDF document text
    • http://septiki-rf.website/duck_hunting_season_2020_illinoisd2tw1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gozotonitiki.epizy.com/toyota_avensis_2007_repair_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a80db94-7c4d-4d2e-86cb-68f13465a851/wipewafasiv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9f3c2ec-18d2-4ced-94a3-4a1d18f28af1/where_is_sydney_airport_located.pdfIn PDF document text
    • http://xagudixuzafet.epizy.com/worship_chord_progressions.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_off0000d038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD038 5524 bytes
SHA-256: 5d004a2b74ab8fc4a6c1439e93b627064514c62dcdbd10921005940ddf4133b2
font_01_sfnt_off0000e2eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2EB 9964 bytes
SHA-256: 426d233992787a945e7c91d6cfabeed76b9c84aea56ef2fa27d71270d466f3fa