Malicious PDF — malware analysis report

Static analysis result for SHA-256 b25756c88de81da8…

MALICIOUS

PDF

81.0 KB Created: 2021-09-22 20:25:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9acf7492a07732f1b2752e27c4c292b8 SHA-1: f8a35992cfb03b0d572c871d7ff94599c1252d74 SHA-256: b25756c88de81da88c77ba0f96f75b192fbed239da98ed4256bae63bb601add1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many pointing to disposable domains, indicating a likely phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript is likely responsible for redirecting the user to these external sites, which are part of a link farm designed to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://seedomoretravel.com/files/files/lixevo.pdf In PDF document text
    • https://pgprojekt.pl/Upload/file/ketulupesirusowiliz.pdfIn PDF document text
    • https://alpinashop.rudy-ra.com/files/51824490181.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/vakoluso.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/makij.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/52286038645.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/zekotadusujisu.pdfIn PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/zupowazamaforavowenozex.pdfIn PDF document text
    • http://haozuowenwang.com/imagefiles/file/tiragigulez.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/56104628198.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/49230398361.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/60921098512.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/63937096357.pdfIn PDF document text
    • https://easresidence.ro/app/webroot/files/userfiles/files/36879203629.pdfIn PDF document text
    • https://santaclara.com/wysiwygfiles/file/rowudenasakedigezajamini.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b5e8d9173---sutinunegesegixojoxove.pdfIn PDF document text
    • http://madonnina.info/userfiles/files/94511081074.pdfIn PDF document text
    • http://progettocecinacuore.it/writable/public/userfiles/file/wuvolopafanow.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/nikuguxelulizixulur.pdfIn PDF document text
    • https://i-chat.tw/js/ckfinder/userfiles/files/30208390445.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/56041162207.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/71381132518.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdbe2c0617---42327844416.pdfIn PDF document text
    • http://takramaipai.com/mypicture/file/gavijuxerabagatijebeb.pdfIn PDF document text
    • http://yyfxsw.com/upload/files/2018975966.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=mac+f5+refresh+chromePDF 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_off0000d225.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD225 10388 bytes
SHA-256: 91c166154a50e20aec77c4c17711f50b1d31c5ea477b518cacd033ba2d7ee772
font_01_sfnt_off0000e9b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B8 20668 bytes
SHA-256: 8b2b4910e5973849eb738f74beb17afd973a5252fd7d7a1e5c54c9c746bb5be2
font_02_sfnt_off00011ed5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1