Malicious PDF — malware analysis report

Static analysis result for SHA-256 a39c1bbafc9989c9…

MALICIOUS

PDF

76.5 KB Created: 2021-09-13 11:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b7afcf8bba485da3c0104a1d426092ca SHA-1: a94095e51d62d2bf3a126e71f853c7d32fc357f0 SHA-256: a39c1bbafc9989c94e0f9417d46ff31453b6246f465b72da1e573d46c9fc1f58
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to link farms or disposable hosting, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML_NYX_PDF_MALICIOUS heuristic also flagged the document with high confidence. While no scripts were explicitly extracted, the structure and numerous external links suggest an attempt to redirect users to potentially malicious sites or to manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 4

  • 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://pastoret.it/userfiles/files/68347208501.pdf In PDF document text
    • https://cissud.it/uploads/ck_editor/files/42248495447.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/83583270180.pdfIn PDF document text
    • http://bacsionline.net/userfiles/file/sipax.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/bobazilogadar.pdfIn PDF document text
    • http://kbcsisa.com/upload/fckeditor/file/94406691502.pdfIn PDF document text
    • https://hssanesteban.cl/files/joxosugefewek.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/96493950772.pdfIn PDF document text
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/wubazaxetutixir.pdfIn PDF document text
    • http://nscenter.cn/upload/files/tujoniluzo.pdfIn PDF document text
    • https://ichapps.peaceofworld.com/ichapps/ckeditor-ckfinder-integration/uploads/files/dezowonegesodej.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/8621532604.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-9-7/20210907225706871775.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/9657585408.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/somup.pdfIn PDF document text
    • http://trivio.it/userfiles/files/jasiweli.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/8294653527.pdfIn PDF document text
    • http://mousike.it/img_ins/files/tavorupirepefedifadakep.pdfIn PDF document text
    • https://www.igescanada.com/ckfinder/userfiles/files/nelamagikokewakuj.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/ba1f32ed0f9330634c8bbdf440242f40/tujisuzonep.pdfIn PDF document text
    • https://www.tvmreza.tv/ckfinder/userfiles/files/wexifemilenosiku.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d6378f31a---92469560917.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/jatufemarajemib.pdfIn PDF document text
    • http://megamento.com/_UploadFile/Images/file/ruzivit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=sword+art+online+alicization+subbedPDF 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_off0000c590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC590 10824 bytes
SHA-256: 43c8aa4df8fd37ab0b3b4b970ae62a038ad091528a2d6d25e0a9dac6c57537e8
font_01_sfnt_off0000deb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB2 17572 bytes
SHA-256: 7e122985374abb4040810c2d0d5172dccbd54dc9019155f9775ec29fadf9d07d
font_02_sfnt_off00010c28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1