Malicious PDF — malware analysis report

Static analysis result for SHA-256 c100aa88c0e43e4c…

MALICIOUS

PDF

68.6 KB Created: 2021-06-08 03:15:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 35fd42849f9a61db1403bfd811740d09 SHA-1: 337b1e8c6868010ee7f6ba258ea5f94af76cfb82 SHA-256: c100aa88c0e43e4c119fc5f1d1083bace141f40e86038aecffdade761a83dcca
156 Risk Score

Malware Insights

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

The file is a PDF document that contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs and link farm heuristics suggest the document's primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://allytemp.ru/uplcv?utm_term=libro+de+irma+fuenlabrada+como+desarrollar+el+pensamiento+matematico PDF link annotation
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/0521277c1a716be2a7dc554249f7b0a3/vavufudomoniwugavuni.pdfIn PDF document text
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/c6f2bb3b94a868f41fcbc87903367075/vatopaligodatejog.pdfIn PDF document text
    • http://namthangbasaltstone.com/uploads/image/files/lavof.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5d94d2646---64714213108.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ab2d032d7---67117326229.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/dbcc60efc27b38f924c9b66a23fa390c/6585552517.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/vomodutav.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ged85i33771rel2147t8ca0qn4/xumegijevipid.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/vflkvpmht94jfabc1qb6vkru2g/61830518029.pdfIn PDF document text
    • https://avenue102.com/uploads/file/47324110869.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607476668664f---bisigiwenabitokoni.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/e9j6evprnvjbcgur9mlps561jf/66421210835.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/huqho1rub1dgemcdo60absivrl/sagunebaderojosekizi.pdfIn PDF document text
    • https://botorka.ro/userfiles/file/84029952043.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-1/20210501095938310819.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16087bc5aa12eb---72215390151.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/80e8b0c471baf34ea14b28fea88d00b7/kuxet.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160732ee8eed1b---luvuvat.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000ceb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEB1 5384 bytes
SHA-256: 756a36265d504f03372d24e03f5dfcaf0399b21deaba22f4dde667fbbd071170
font_01_sfnt_off0000e0e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E7 10396 bytes
SHA-256: 4fa5611085676d02f3d50d01f425374845775874d75c6e9a761a2823f99aacbd