Malicious PDF — malware analysis report

Static analysis result for SHA-256 b319128032740703…

MALICIOUS

PDF

69.4 KB Created: 2021-09-29 10:56:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 78085f630cdf228825bf643a971631a9 SHA-1: 7aa42aa2538b5a82706a6ccbf27873ed121cfd64 SHA-256: b319128032740703ecf24e3895c40d4f547be53debad7cd79875981e20bc7015
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to potentially malicious domains. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a pattern of using disposable hosting for link farms, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://perfecthospital.net/ckfinder/userfiles/files/58451761948.pdf In PDF document text
    • http://tingchucontrol.com/Uploadfiles/files/loliridegeganimidelexe.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/gofulividuvutowimofem.pdfIn PDF document text
    • http://hjtech.org/admin/upfile/file/95456470463.pdfIn PDF document text
    • https://joinvita.com/neu/userfiles/file/92233170509.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/38070911502.pdfIn PDF document text
    • http://theffirm.com/userfiles/file/lakixer.pdfIn PDF document text
    • https://nhatngudongkinh.phapluatvietnam.com/upload/ckupload/files/50376097877.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/sevupavubiluvolijikalefe.pdfIn PDF document text
    • http://beijingteye.com/upload/files/jikerik.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/solubatipebareluzixagog.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/rutufazuvovawasix.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/fuzim.pdfIn PDF document text
    • http://nguoiquangphianam.com/uploads/files/51791046469.pdfIn PDF document text
    • http://office-tommy.com/images/file/zelesixakimukipep.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614f05199c3fd---gumar.pdfIn PDF document text
    • http://matraholding.hu/images/userfiles/files/98638369350.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/jefarikususozo.pdfIn PDF document text
    • http://classiccar-jp.com/js/upload/files/27526212050.pdfIn PDF document text
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/50846136792.pdfIn PDF document text
    • http://alcantara.cz/data/file/lawudagalupokezekuxubo.pdfIn PDF document text
    • http://talleresjpg.es/img/file/33132767232.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/53638088885.pdfIn PDF document text
    • http://top1np.com/ckfinder/userfiles/files/nalupefokujuxozeto.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/77275528967.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=is+chromecast+an+android+devicePDF 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_off0000b055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB055 15480 bytes
SHA-256: 898100c90103bcaabdc70d136e9c1aee9a3af61ec878baf91df5a58fcb672045
font_01_sfnt_off0000d7be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000efd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD5 10608 bytes
SHA-256: 44681557fc4544496a97efc27355b5d914caa2f73cb5fb392fc7c64d77f60c61