Malicious PDF — malware analysis report

Static analysis result for SHA-256 b84d82e6f3cb55c7…

MALICIOUS

PDF

77.1 KB Created: 2021-09-15 21:57:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ff5f22b95c45f804bd5b6740a24bcc97 SHA-1: 707ed0fbdd90137547caefe8634fa23623d75aa1 SHA-256: b84d82e6f3cb55c74bf6edbf385df5499811b940d1b384946fef4b5536cbe8d8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to potentially compromised websites or disposable hosting. Heuristics indicate it's a link farm on disposable hosting, and ClamAV detected it as Pdf.Phishing.Trojan. The ML classifier also flagged it as malicious. The primary function appears to be redirecting users to external sites, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://salamino.pl/userfiles/file/sumokalewomabomopekowo.pdf In PDF document text
    • https://ispartaprefabrik.com/ckfinder/upload/files/robunifa.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/rokab.pdfIn PDF document text
    • http://samtekelektrik.com/files/zerovekubefajupezawapepil.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613219e0203bb---25873761513.pdfIn PDF document text
    • https://wigs4less.net/nbloom/fckuploads/file/wixalokonutojowo.pdfIn PDF document text
    • http://hoangle.vn/uploads/userfiles/file/71132074943.pdfIn PDF document text
    • http://tokyo-sanritsu.com/userfiles/file/xepunipewelene.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/46789171571.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/65749657640.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/sukojotibogi.pdfIn PDF document text
    • https://perfecthospitals.com/FCKeditor/file/delonaxud.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/20219101551519187.pdfIn PDF document text
    • https://slicktechproducts.com/newerac2c/userfiles/file/78504720946.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/76699789273.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/7v2lr58muvaimqbl1roqkqlasb/viwoxikasoxivadaben.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/xebivajudevim.pdfIn PDF document text
    • http://uniontsg96.ru/admin/ckfinder/userfiles/files/19739212848.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/29ae4241d87640842f9f6accbbabd7de/89029838267.pdfIn PDF document text
    • http://uslugi-ogrodnicze.pl/pliki/File/67596238849.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/bizozi.pdfIn PDF document text
    • https://eventpro-kontraktorpameran.com/uploaded/files/63302294402.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/14187885400.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=f+se+10+wordPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cdc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC3 16652 bytes
SHA-256: a5c159eacf7c29647cda086f8a32f6804c20a9506f31f9b40bf65e9773ef8203
font_01_sfnt_off0000f8e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FC 9976 bytes
SHA-256: db6fc69ec53af2a7ebcf146fcf8db9c161f48d7c77f42acd22f5368262919508