Malicious PDF — malware analysis report

Static analysis result for SHA-256 f91745ecb119cd95…

MALICIOUS

PDF

78.7 KB Created: 2021-09-12 11:59:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 81030419be90d204b6c30be00391e68e SHA-1: 1336f7a0ebb760fa8e707435854b2c6b806db86b SHA-256: f91745ecb119cd95e028a37bca15c78ae7319dfe71ff8ffb1bdf48361dea5f9e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that redirect to other PDF files hosted on disposable domains, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious classification. The presence of embedded URLs and the nature of the heuristics indicate a phishing attempt to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://philabc.ru/uplcv?utm_term=download+asphalt+9+play+store PDF link annotation
    • https://censcakmu.org/board/file/files/38031000618.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/bimanadi.pdfIn PDF document text
    • https://vivekanandbawwa.com/userfiles/file/46565537357.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/babitigajosiguk.pdfIn PDF document text
    • http://epwuae.com/userfiles/file/63552232053.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/xokowuf.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/58622538721.pdfIn PDF document text
    • https://scavilecis.it/userfiles/file/vezaf.pdfIn PDF document text
    • http://simoncaulkin.com/images/32447105881.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/13502677085.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8424dd8a1---nulebisarunorosukaran.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377b8820069---legifoleruzate.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/48071409344.pdfIn PDF document text
    • http://americansemitruckparts.com/d/files/desimozegusozimatop.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/66354503607.pdfIn PDF document text
    • http://phukientubepxinh.info/gomsu/sanpham/anh/files/wuponirarufof.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///kekokiwomilosejixav.pdfIn PDF document text
    • http://progettocecinacuore.it/writable/public/userfiles/file/79887951614.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/rigawufuvemoberotoxije.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/41674683986.pdfIn PDF document text
    • http://www.oomewatersport.nl/upload/files/zewanofozodavajixamafara.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/vodumam.pdfIn PDF document text
    • http://shangyi-pump.com/uploads/file/032256271415.pdfIn PDF document text
    • http://sweatrinserepeat.com/ckfinder/userfiles/files/11014130940.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/33889413361.pdfIn PDF document text
    • http://ros-audit.com/i/up/file/bakukimozote.pdfIn PDF document text
    • https://zapcdn.space/web/img/podborky/files/98699707784.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_off0000d1d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D9 16412 bytes
SHA-256: dff2e2fbff8bae3c16c2a8f77892062a64393bcfcb9c5e8765915eac3fdb6029
font_01_sfnt_off0000fbf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001140c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1140C 10764 bytes
SHA-256: 629cf1675d8b1374f0b3fe1e25006b34607b8dc0438f78f79ccf6e52342c1c68