Malicious PDF — malware analysis report

Static analysis result for SHA-256 b411ec8631b37992…

MALICIOUS

PDF

81.3 KB Created: 2021-09-22 12:18:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 04d057df681c097db84b483f255774dc SHA-1: 4297785b3dcd3d6fdec8975839e01eac168ffe89 SHA-256: b411ec8631b379923a9b447cd84fefb4fa223cb7f7d2c21abcf8fc3f231d1c74
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to lure users to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://hiroshima-teishaku.com/userfiles/file/73425684631.pdf
    • http://teplorium.su/userfiles/file/36346494010.pdf
    • https://portalkucharski.pl/app/webroot/media/files/nujebusavukegepekivole.pdf
    • https://traiteur-troyes-mariage-buffet-aube-10.blaisot-traiteur.fr/ckfinder/userfiles/files/3158475294.pdf
    • http://bosch-elektronarzedzia.pl/catalog/file/65458588345.pdf
    • http://whatdwellswithin.com/file/42921114221.pdf
    • http://emilygrilltogo.com/uploads/files/kugekil.pdf
    • http://www.horakgolf.cz/ckfinder/userfiles/files/kesulagikevites.pdf
    • https://epagneuls-bretons.fr/caningest/images/file/mepezazudavipuxuvumuriri.pdf
    • http://fd-health.com/upload/ckeditor/files/banawifigipimu.pdf
    • https://marblobath.marblobaths.ph/app/webroot/img/files/99268325749.pdf
    • http://eikenhorstgroep.nl/userfiles/file/6987691548.pdf
    • https://semut73.com/contents/files/sobov.pdf
    • http://dongsimkindergarten.com/upload/files/33279283737.pdf
    • http://soft-pro.hr/upload/datoteke/37984193760.pdf
    • http://dongtienlamnghiep.com/upload/file/73094532981.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/50263d20e3f4240ac11ed86db1b734a0/nozasuxu.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/sjj8oslu5he7013i8n2b9p3pn9/47522861234.pdf
    • http://flairpens.ru/uploads/file/20165089819.pdf
    • http://boothbayharborshipyard.com/userfiles/file/5029073944.pdf
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/18194134374.pdf
    • http://ktcyy.com/ckfinder/userfiles/files/lamuf.pdf
    • http://z-him.ru/userfiles/file/ruwujosexegulikumapigifi.pdf
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/raxifujakatenuzov.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=transfer+phone+contacts+iphone+to+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9cf.bin
af0ca9d5b5c7d09cbd81fee3420ec53f6a708112df671e3e69872dda68b95ef3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CF 10636 bytes
font_01_sfnt_off0000f212.bin
93cb396f028eb544a397b3ad281505ac08060a8079bdb64abae37b5952fafd5b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF212 17220 bytes
font_02_sfnt_off00011f3a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F3A 16792 bytes