Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce2621dfc472f79e…

MALICIOUS

PDF

93.3 KB Created: 2021-03-22 16:20:12 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 2837521bf7e23fb8ce0a2fbd57608e4b SHA-1: 200d4d5989892c39c01bfb28e6cad2bff9e64b0f SHA-256: ce2621dfc472f79e4eb3bc0f10cec80423723ae72338773f50b949b1bf06ac6b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains text related to 'deep learning' and 'activity recognition', likely used as a lure to disguise the malicious nature of the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://maypoin.ru/strik?utm_term=multimodal+deep+learning+for+activity+and+context+recognition PDF link annotation
    • https://fugagabek.weebly.com/uploads/1/3/1/4/131453631/6041818.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468540/normal_6029296edffe5.pdfIn PDF document text
    • https://fubexomufepa.weebly.com/uploads/1/3/4/8/134850999/vimusilimorudi-ruborotabudi.pdfIn PDF document text
    • https://cdn.sqhk.co/dijowasedop/jPDDwid/mefelilomerezono.pdfIn PDF document text
    • https://kusafowagu.weebly.com/uploads/1/3/1/8/131871480/4336a.pdfIn PDF document text
    • https://tariroviwobin.weebly.com/uploads/1/3/4/7/134715354/safiwutujipum.pdfIn PDF document text
    • https://vaseviga.weebly.com/uploads/1/3/3/9/133986607/9f70518814.pdfIn PDF document text
    • https://mujujexeko.weebly.com/uploads/1/3/4/6/134630432/aa81ceb.pdfIn PDF document text
    • https://cdn.sqhk.co/resozasevej/5hfijKe/pojoxiripipidurego.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483873/normal_5fd0e552571bf.pdfIn PDF document text
    • https://bivesazi.weebly.com/uploads/1/3/4/6/134652180/turaxil_kovutafupewogus_mufimibanovez.pdfIn PDF document text
    • https://sezorataxij.weebly.com/uploads/1/3/4/6/134600708/loremuzagobuzek_sigirijepazo_zesigomufolixa_bipegedaw.pdfIn PDF document text
    • https://teduminerat.weebly.com/uploads/1/3/4/6/134665194/tiwodevutobipi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422133/normal_60406b2de973d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449205/normal_6044fc44ab2f3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379605/normal_602f1632342d5.pdfIn PDF document text
    • http://womotov.22web.org/4354118649.pdfIn PDF document text
    • https://cdn.sqhk.co/wosipuvetot/ufgdM6p/java._lang._outofmemoryerror_java_heap_space_in_tomcat.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/likerajatob/el_anarquista_coronado.pdfIn PDF document text
    • http://nudenagazosizav.epizy.com/biomass_fuelled_power_plant_abstract.pdfIn PDF document text
    • http://konimeva.rf.gd/32386706182.pdfIn PDF document text
    • http://zilokujidetomo.epizy.com/pulimodak.pdfIn PDF document text
    • https://s3.amazonaws.com/gowebabuxogiro/65881860014.pdfIn PDF document text
    • https://s3.amazonaws.com/kudufigunabi/annotate_on_onenote.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011e80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E80 5412 bytes
SHA-256: 9da078986e7716fba4bfa70254c2bd02346772559559e849a953e0a910d06082
font_01_sfnt_off000130ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130EA 12680 bytes
SHA-256: a7ee2e3af791bc3933f2f2f28f2c18850d04e0f4d77e5bc7f62c55e8e0c1718b
font_02_sfnt_off00015899.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15899 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361