Malicious PDF — malware analysis report

Static analysis result for SHA-256 82f57563a05c4ba2…

MALICIOUS

PDF

71.4 KB Created: 2021-09-15 12:22:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 85f326cd8e5843936bdaf4b8661ebc86 SHA-1: bbe700a20b5b42bd4e62f90a1c9ac6d8d2e994dc SHA-256: 82f57563a05c4ba2dd1a8c4b38feb75e7c5eabd460b355804559ecb917484386
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. It contains numerous links pointing to various domains, many of which appear to be disposable or compromised hosting, forming a link farm. The presence of external URI heuristics and the 'PDF_SEO_DISPOSABLE_LINK_FARM' rule indicate a strong likelihood of this document being used to redirect users to malicious sites, potentially for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://smidgel.ru/uplcv?utm_term=grammar+and+beyond+3+teacher+support+resource+book+pdf PDF link annotation
    • http://fine-cottage.ru/userfiles/files/sazobevesujujutisijagilo.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///80150825281.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/42160003376.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614071273d663---vezumijejotobope.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/sosanopomukafanepo.pdfIn PDF document text
    • https://happyjourney.webtrails.in/ckfinder/userfiles/files/sozitaxadaloxuwusonorulo.pdfIn PDF document text
    • https://myreply.mobi/snappshott/editor//file/63671619130.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/rimepekigofuvufobawulag.pdfIn PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/12262596370.pdfIn PDF document text
    • http://altus.pl/userfiles/file/30946249214.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/33978158983.pdfIn PDF document text
    • http://jca-t.com/fck_image/file/pafore.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614165c9c2a7b---kuwon.pdfIn PDF document text
    • https://bonvoyageindia.in/ckfinder/userfiles/files/15776027737.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9d2fc08cd---26821086252.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/tapuxawili.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/76809248016.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/55733050494.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b23cf80dc9---puzovezixofiwu.pdfIn PDF document text
    • http://bidadapatidar.com/userfiles/file/17715293352.pdfIn PDF document text
    • https://wwa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/welozegizumupaz.pdfIn PDF document text
    • http://kvrhousing.com/uploads/30170819937.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://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_off0000b18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB18A 11404 bytes
SHA-256: 91801dfefcea1511f2d9a36907d4710f2534e1f7f4cce4d8df46c0f2784e8b7d
font_01_sfnt_off0000cc1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC1F 16944 bytes
SHA-256: 6278cda3ebe6bba6502389586f8fe5c82c43ac734d9b4dce59a6347a6fc0ce8e
font_02_sfnt_off0000f761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF761 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1