Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d27c097a49f579…

MALICIOUS

PDF

79.0 KB Created: 2021-09-12 11:15:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a40ef5077cfa2af5321976e81f88fd5f SHA-1: cef4be817366652cca8d366eeb40391649481f25 SHA-256: 81d27c097a49f579450292138235f8df9740436fa307c2b27c06634b4e8996de
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm on disposable hosting, suggesting a phishing or credential harvesting campaign. The presence of embedded URLs and the nature of the heuristics point towards the distribution of malicious content or redirection to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://chcial.ru/uplcv?utm_term=pixel+software+updates PDF link annotation
    • https://qatarsecurityservices.com/public_html/userfiles/file/kulozulevadoxomusami.pdfIn PDF document text
    • http://canphantich.net/Images_upload/files/goxexinupofeleb.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/sinajajiwewamejexewazomib.pdfIn PDF document text
    • https://letstravelforacause.com/miet/assets/files/5533485569.pdfIn PDF document text
    • http://vlajamo.cz/images/file/72394896508.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613704e4b69cf---16984716885.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/xavixelafote.pdfIn PDF document text
    • https://rajatotogroup2.com/contents/files/moraboputatuxuruke.pdfIn PDF document text
    • http://yds-wcv.jp/free_images/files/bojenunosunabobilas.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/subijapelofoputabozu.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/feveluzitagimevitaw.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/5edcb61dda839f7921e223c7d2688a62/5976856734.pdfIn PDF document text
    • https://littleedupark.com/ckfinder/userfiles/files/muvosokopagamomezug.pdfIn PDF document text
    • http://squash-fitness.cz/userfiles/file/desavokufe.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/64939956273.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/dusesufurufiwod.pdfIn PDF document text
    • http://pbpharm.com/upload/files/5824589661.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/dedidifalud.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/10379205213.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/sevogunexopibuvufajilu.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109051637589746.pdfIn PDF document text
    • https://sanmuabancongty.vn/images/content/files/46271001338.pdfIn PDF document text
    • http://mylivediamondinventory.com/uploads/files/97166962924.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/34408750056.pdfIn PDF document text
    • http://lica-mpt.it/userfiles/files/66143166876.pdfIn PDF document text
    • 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_off0000d142.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD142 17044 bytes
SHA-256: c6582ea7901464e3c5012c563bf309557110959ed6b1d1c6a484e277ca5776b1
font_01_sfnt_off0000fd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001158c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1158C 10676 bytes
SHA-256: 19b8926fb515e0d0649cdceb20cb35ac5871250d625f9b9f3b61aca50d8f09e9