Malicious PDF — malware analysis report

Static analysis result for SHA-256 91eec5688a6f4e00…

MALICIOUS

PDF

74.9 KB Created: 2021-03-31 09:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: df4f344936e4c16ff36ac8469670160d SHA-1: b86ba44b5dfa92ed3e92013d196907034867ccd2 SHA-256: 91eec5688a6f4e00cda30fdc2f8b52b2e4e41bfc5e453e66d06ee258a44729f0
126 Risk Score

Malware Insights

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

The PDF file contains multiple embedded URLs, with one specifically pointing to a 'keyword' search related to a 'cognitive ability test'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of numerous links, some on disposable hosting, suggests a link farm used to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://baarspo.ru/award?keyword=general+cognitive+ability+test+telkom+pdf PDF link annotation
    • https://kotuposa.weebly.com/uploads/1/3/1/4/131406283/2959196.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446915/normal_604d3dbea1569.pdfIn PDF document text
    • http://gomijexa.mywebcommunity.org/b._l._theraja_a_textbook_of_electrical_technology.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370780/normal_605530428fc71.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465914/normal_605173b6f31fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426422/normal_6063cac70d802.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451033/normal_600993980abe5.pdfIn PDF document text
    • http://zunanifuxomo.iblogger.org/lebowumura.pdfIn PDF document text
    • https://guvepilafofifiv.weebly.com/uploads/1/3/4/6/134682232/4172269.pdfIn PDF document text
    • https://xewoxexe.weebly.com/uploads/1/3/4/3/134398473/9178634.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/dewutexorob/examples_of_self_appraisal_comments.pdfIn PDF document text
    • http://fusozevukatamir.atwebpages.com/tixora.pdfIn PDF document text
    • https://33edd578-4186-4695-89f3-f56a5a23fc53.filesusr.com/ugd/f17c08_c9842535356143c9a6bf9e973b775e66.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nowokil/couchdb_query_performance.pdfIn PDF document text
    • https://s3.amazonaws.com/fupanabivote/todifutalutuma.pdfIn PDF document text
    • http://vedixemalirugi.atwebpages.com/48460727228.pdfIn PDF document text
    • https://4900ecec-7ac1-411c-be2c-b077674085c8.filesusr.com/ugd/493135_ed1cf9f08ee34a7c91d14fdbc59ea648.pdf?index=trueIn PDF document text
    • http://dinotowiteve.rf.gd/2633176126.pdfIn PDF document text
    • https://s3.amazonaws.com/fajixe/wojagefiwisojomenowexa.pdfIn PDF document text
    • http://fokobawenola.epizy.com/bepilodarunukamemenek.pdfIn PDF document text
    • http://gejaxogepokotow.rf.gd/33499869029.pdfIn PDF document text
    • http://nolixegoxow.epizy.com/sojanasedarokomasar.pdfIn PDF document text
    • http://taberadajip.atwebpages.com/29406619792.pdfIn PDF document text
    • https://s3.amazonaws.com/pazatuv/how_do_i_adjust_my_cpap_pressure.pdfIn PDF document text
    • https://e6c529cc-411f-4195-b5ea-7b5fd081490a.filesusr.com/ugd/b7ab08_735950358c5248d79da31e02496fec98.pdf?index=trueIn PDF document text
    • https://9005a25f-7293-4a73-bb0f-bc58e8c16807.filesusr.com/ugd/e3834b_0564ecdbef814f238b18352ec389417a.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_off0000e449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE449 5872 bytes
SHA-256: 0c3d74c2f3b00a3c710932223bc324e84ed86e85fdf84f78f794af52c8fb9c4a
font_01_sfnt_off0000f843.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF843 11052 bytes
SHA-256: 9502ff1b147903508b782f4853ef27117c636a3cf0a88d894de11a9dd2d24f5f