Malicious PDF — malware analysis report

Static analysis result for SHA-256 5513af31c4be8a59…

MALICIOUS

PDF

75.9 KB Created: 2021-09-12 14:04:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7bd5a47d2656b1fcff2e6d9f802ae1f2 SHA-1: 090b278564ebf0fc5dd4aeac28e2114272c3c823 SHA-256: 5513af31c4be8a599a662c5e75adc687b061d312da1e77fc23ac1070f9a894ea
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for a large number of links, reinforcing the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 http://www.dgtrans.co.th/login/ckfinder/userfiles/files/lumuj.pdf In PDF document text
    • http://tuzvedo.hu/elemek/file/97316781167.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/xabame.pdfIn PDF document text
    • http://kmkonsult.cz/userfiles/file/61615188584.pdfIn PDF document text
    • http://kerekesvillszer.hu/UserFiles/file/11218146107.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613861c70f3bf---fozizonekakosuremezola.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/15862212710.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/zobin.pdfIn PDF document text
    • http://fnathservices.com/upload/file/pupowu.pdfIn PDF document text
    • https://bhandarisurgical.com/ckfinder/userfiles/files/87222675881.pdfIn PDF document text
    • http://biosite.ru/images/news/file/wewilona.pdfIn PDF document text
    • https://tonthephunglan.vn/upload/files/vadubu.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/93735827842.pdfIn PDF document text
    • http://trongtinpc.com/luutru/files/44509706007.pdfIn PDF document text
    • https://exam11.menapoint.com/app/webroot/upload/files/sabepasafokasowolemaje.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/jemidowusamokipiwulu.pdfIn PDF document text
    • https://rowanmkt.com/Uploads/ckfinder/userfiles/files/3659163385.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/wotam.pdfIn PDF document text
    • http://websteravelandscaping.com/editorData/file/43099802896.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613595851de2d---99813756226.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/68739546207.pdfIn PDF document text
    • https://greenlakepaint.com/ckfinder/userfiles/files/nifunefemimujebesofulu.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/faparovi.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/5373013228.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/saxolaresawi.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50369778890.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/lipitejogekakivujutemi.pdfIn PDF document text
    • http://potentialdesign.cn/userfiles/file/1631055291.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=wcc2+mod+appPDF 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_off0000c5ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5AE 10048 bytes
SHA-256: 8f94c7991226d9813f73a426e32cbec71794f2c1d87d077713a5271caf832a61
font_01_sfnt_off0000dc14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF426 17776 bytes
SHA-256: 9bfcf725b97a726c7b50f7c6835637c1ecc3cfec42efc01d67d1f886926a8329