Malicious PDF — malware analysis report

Static analysis result for SHA-256 f836c882c27a4b92…

MALICIOUS

PDF

76.6 KB Created: 2021-09-18 04:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: e008cee17bdfac0cf5d27b2a1d5c0326 SHA-1: 9d4e61b5d098efd99f70576745576518d417e1ca SHA-256: f836c882c27a4b92fa7f92969744d72caa32c8abb871a9bb4c38aaf5a6f2e4c5
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs, many of which point to disposable domains. The ML classifier strongly indicated maliciousness, and the heuristic for a link farm on disposable hosting further supports a malicious intent, likely for phishing or malware distribution. The embedded JavaScript could be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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 http://vonschickenfremont.com/uploads/files/2772287408.pdf In PDF document text
    • http://sanzmendia.com/userfiles/files/91806551856.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/vafipisapamom.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/setupewabezavufibesimos.pdfIn PDF document text
    • https://linlinline.biz/js/ckfinder/userfiles/files/tikifuxonivezirilunuveked.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/0btao9reut32mpuokrtseh7kqi/85788231242.pdfIn PDF document text
    • http://mydreamtuscanwedding.com/editor_up/34696762307.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70321022532.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/50778131445.pdfIn PDF document text
    • https://micsys.in/userfiles/file/fodupopanalimifebirut.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210917035047.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/95104565404.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/19005888045.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/73336574299.pdfIn PDF document text
    • http://seychelles-resort.com/images/blog/file/gekugupuxanagi.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/ropedirebipefafebalip.pdfIn PDF document text
    • https://smartech.lv/sites/smartech/uploads/documents/files/vetajumozijazef.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud/files/lanesinafuzugobopa.pdfIn PDF document text
    • http://sozopolihills.com/userfiles/file/9683003701.pdfIn PDF document text
    • http://suaups.net/userfiles/file/zosevap.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305fe250a9e---vilezexeduxijexenazufelu.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/99925440979.pdfIn PDF document text
    • https://huuphongplastic.vn/uploads/images/files/56436517087.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=unblocked+lol+1v1PDF 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_off0000c8c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D9 10100 bytes
SHA-256: d505436c6185c90a8ad509da23dd8a8ca73cfb0e53003b05585e39e4ebd7e17d
font_02_sfnt_off0000f77d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF77D 17436 bytes
SHA-256: b33c2b8200994449a5108690685417d3668f17c78cd866bd02524914da55ade3