Malicious PDF — malware analysis report

Static analysis result for SHA-256 c901f92356742575…

MALICIOUS

PDF

74.8 KB Created: 2021-03-28 11:15:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 0c8dc8efed190732cbe312b7c565c0af SHA-1: 056ca85b755aa97270d7f536cd224406114a4772 SHA-256: c901f92356742575c2c763a35bd0ba93a2388db83e553e3659915a71e2ef15a8
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm, with several pointing to potentially malicious domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://zajinet.ru/strik?utm_term=how+to+change+temperature+on+a+thermostat PDF link annotation
    • http://susurrus.space/hatchimals_colleggtibles_season_4_waterfall0qpi8.pdfIn PDF document text
    • http://kafikiwamavo.22web.org/37186930769.pdfIn PDF document text
    • http://claire-irk.ru/how_do_gods_get_their_powers42hw8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413578/normal_60595cd18942d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381531/normal_5ff8a72d2cc63.pdfIn PDF document text
    • https://pakupefo.weebly.com/uploads/1/3/0/7/130776676/kuxupe.pdfIn PDF document text
    • http://kugenezajiz.22web.org/plant_virology_hull.pdfIn PDF document text
    • http://ppl-nutrshopfit.website/75782423485o55p1.pdfIn PDF document text
    • http://neyroskakalka.site/backflow_inspection_reportvm5u1.pdfIn PDF document text
    • http://bomufofo.iblogger.org/bethel_king_of_my_heart_chords.pdfIn PDF document text
    • https://ponuwusareti.weebly.com/uploads/1/3/1/6/131636782/4489657.pdfIn PDF document text
    • http://podcard2020.site/spalding_basketball_goal_partsrlmdy.pdfIn PDF document text
    • https://dapobirot.weebly.com/uploads/1/3/4/8/134888013/zujexa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fuxalobel.rf.gd/jovurilu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16042e68-db39-4b81-9b52-ff0df82754c6/dell_2005fpw_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4cad1df-eefe-42e2-a8e0-66ac26325af6/vepokapemafixodituxutexun.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa306287-2ef0-4c86-a540-87dd7602cfc0/how_to_say_thanks_in_ghost_of_tsushima_legends.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a463c06e-65d2-4b2c-a31c-ebe3e5ae345f/jufana.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d0219f79-05c3-4b6b-bd7b-56add7f1d2b0/maytag_2000_series_washer_error_codes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c2618d8-9fc2-4ae0-bfdf-c61142586f3b/45044161276.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e1d4215-1e48-45b1-a272-84aa28a2c437/casio_wave_ceptor_manual_3140.pdfIn PDF document text
    • http://pagolojesuwagi.epizy.com/gixukaxadex.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_off0000e6bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BC 5368 bytes
SHA-256: 0e1638d4efdff37d58cd636fb1e5e50a01182d6481b30ea43361104019e6dd49
font_01_sfnt_off0000f8e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E6 10712 bytes
SHA-256: 1aa5abbc257b6f8ac4ac629853b39a46f0735cd4d51d0b5fdc72264a940b5ea3