Malicious PDF — malware analysis report

Static analysis result for SHA-256 243bcce138c8ca7c…

MALICIOUS

PDF

84.7 KB Created: 2021-09-20 01:07:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8b1b59e9a6d43639fe88e44466cc91c2 SHA-1: 2abade77a2601f7d4305696c27ce47d0eac8390a SHA-256: 243bcce138c8ca7c1b7815157895443be8d08362d39e10a6048d9cf97b948d26
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially malicious content. While no scripts were explicitly extracted, the PDF structure and the nature of the heuristics suggest it is designed to redirect users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://matao.ro/app/webroot/files/userfiles/files/76982670520.pdf In PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/livokagalo.pdfIn PDF document text
    • https://easresidence.ro/app/webroot/files/userfiles/files/35469203662.pdfIn PDF document text
    • https://derfo.info/resimler/files/wumubigoviwarirelorina.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/jodofivitasigeduwuvi.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/80693662130.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/38134023127.pdfIn PDF document text
    • http://taiwanquinoafamily.com/shopadmin/upload/files/laziz.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/pnc78q7bbq0locs3kq2u9dlhdg/75952740161.pdfIn PDF document text
    • http://needychild.org/ckfinder/userfiles/files/dojegitogado.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/79473839834.pdfIn PDF document text
    • https://profm.hu/files/file/salobibowa.pdfIn PDF document text
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/bofutivatowategak.pdfIn PDF document text
    • http://email-database.info/userfiles/file/mulerotubedusobebetajidu.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/nixamufa.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/55942911472.pdfIn PDF document text
    • http://szcftz.com/upload/45441343479.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/rexuxupu.pdfIn PDF document text
    • https://pr-dienst.ch/file/kakijozajamidifadubamab.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/9208939069.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/161328a40366c4---sudalik.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/67946443787.pdfIn PDF document text
    • http://paneldeconso.com/userfiles/file/zabademuri.pdfIn PDF document text
    • http://perchegouet.com/ckfinder/userfiles/files/javovuvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=videoder+latest+version+14.3+downloadPDF 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_off0000e6b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B1 10728 bytes
SHA-256: 28f1912c32d0a16ede39ea806fc1cd143d0e338a6d8bcad83cf1d04415748280
font_01_sfnt_off0000ff9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AD 17280 bytes
SHA-256: 9917f2f76799796783cb58e5e24e33a124cd90a377e993063c50167e36f8fb5b