Malicious PDF — malware analysis report

Static analysis result for SHA-256 8651e65cea7fa2e8…

MALICIOUS

PDF

69.4 KB Created: 2021-09-27 11:59:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: acf0598cc2a5904c431802a24cccdcab SHA-1: 9b8cd4655df4b440f5df2b876f4c48b0d4e75d3d SHA-256: 8651e65cea7fa2e8c8a25285f3ce33725afb0ede4ce5b6ae6fbc52274e46e129
126 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains a large number of embedded URLs, many of which point to disposable hosting and appear to be part of a link farm. The primary function seems to be redirecting users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chcial.ru/uplcv?utm_term=anugraheethan+antony+torrent+magnet PDF link annotation
    • http://emailreceptionist.net/userfiles/file/tubibejol.pdfIn PDF document text
    • http://1night2daytour.com/ckupload/files/fumiroguxebut.pdfIn PDF document text
    • http://ppfi-online.com/userfiles/file/41873018089.pdfIn PDF document text
    • http://tarnava.eu/user_images/file/wexakuxetuxa.pdfIn PDF document text
    • http://juentai.com/userfiles/files/madowime.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/sugenabivokavekuxi.pdfIn PDF document text
    • http://mweb.cz/images/file/dirikerosukopiwowasepodot.pdfIn PDF document text
    • https://poulinstrapscan.com/userfiles/file/xupimotadawegemijib.pdfIn PDF document text
    • https://ist-lb1.istanajp.com/contents/files/81408711458.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/34629900897.pdfIn PDF document text
    • https://dnm.tw/uploads/files/202109111225096156.pdfIn PDF document text
    • https://vanchuyensahara.com/site/files/sumijevoli.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161464c1f32811---70371406886.pdfIn PDF document text
    • http://officinedesign.it/userfiles/files/fodibusaxe.pdfIn PDF document text
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/27681483177.pdfIn PDF document text
    • http://zima.italie-ubytovani.cz/data/file/30661101157.pdfIn PDF document text
    • http://96rangjai.com/userfiles/file/kelixagodomeremidafav.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/82812024612.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/zapem.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210904145031.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/82605599964.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109050409395858.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/55798957550.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/tuxatirorax.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/fc62f853fb0c6820b3c80dd08b98f2d4/62521055570.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_off0000b064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB064 10444 bytes
SHA-256: 2839debba1afdfa92339e4320b2d18e626d46c77979ea3f75a60876bb41c49e8
font_01_sfnt_off0000c7f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE004 15700 bytes
SHA-256: c3d48e6370a8208b31c4110e516d2cba45e9d2ad43ed262a0847039578da60f4