Malicious PDF — malware analysis report

Static analysis result for SHA-256 636436a89939b8a8…

MALICIOUS

PDF

103.9 KB Created: 2021-06-10 15:57:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 2048beefb62328ce17f1c465580fe5c9 SHA-1: bcdaedc67c93dd92282b3293fc4c0ad302fba783 SHA-256: 636436a89939b8a81e5dbc39ac19c6eb3993d00ff53a449c3a02d76052621c59
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://philabc.ru/uplcv?utm_term=kanthar+sashti+kavasam+pdf PDF link annotation
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16098986233a55---41033320439.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/621e75793b20f3ecb82ce4cb967d4af3/62064189120.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/49854305320.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/0jl1qnkbp0o83l9rom5lh3v315/30942324259.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/68852323804.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/80db7ac1131c7a4047b5e007c84b61f9/84784627713.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/vinad.pdfIn PDF document text
    • http://growlink.biz/userfiles/file/gefuzolaxipulejuzex.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/2b147dca96da4fde69b75504971b4398/kiwudixow.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/184e81901cbc4f81b6dc35bae35a2575/78137414805.pdfIn PDF document text
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/fbcb7a6233961019a4f45c6aaccf07c8/55885294622.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/62784802bcef8b9eff24300fb3b3ad43/xoloxodunozupi.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/dupagibus.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/71a15278b8a2037e07f74b9401735452/lolikegekopos.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off000137ba.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x137BA 27120 bytes
SHA-256: 6832666a1424d9e89067dcffe773356507c7045b8a036da01c1456e30de0ccd4
font_00_sfnt_off000125b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125B6 5344 bytes
SHA-256: c061473fc037b477b84568ca5aa39c0d2fd43b4b9d7569f3e7fdf295f0a523df
font_02_sfnt_off00016de7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DE7 11076 bytes
SHA-256: 1db50abdef5e5a34fe90abc52a42bc3c59bdbcf7a38335149c021e6ca9df6e30