Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9d43c43ad0d3519…

MALICIOUS

PDF

77.4 KB Created: 2021-08-07 03:32:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0fc374565328ada17a6c870a79cfccc5 SHA-1: 9b9bcaba7d965ad5bedc9d3703f4925a5295a832 SHA-256: f9d43c43ad0d35192b85a2c5b3002a44747f82643a060580972cd8610eb152a2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to compromised WordPress upload storage and other potentially malicious domains. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pametnidom.hr/pametne_kuce/userfiles/file/tefefefaluzumep.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16077d361678a8---juvugufigatuvazosowalelu.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2e70ce5e4---gobavuwujejenagitozibu.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/dc7c9fe067a5b93dc7cae136fce42385/mogozajulaguxote.pdf
    • https://familienarbeit3plus.ch/userfiles/files/nodeloxanevovi.pdf
    • http://kapsalonindex.nl/images/uploads/21931487031.pdf
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/9c5lkd3k39k5tlug10b29r8ja4/ziwanozujarefiv.pdf
    • http://budohurtsa.pl/userfiles/file/zinezodesidemanewoxu.pdf
    • http://www.deewanalarab.com/up_imgs/83956891235.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1610dbeb2a0bbf---59017962389.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/6c84c448b8ee52a7ec3c54b7cae4ed0a/sabazuru.pdf
    • http://cancercareresearch.com/userfiles/file/3252239432.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f216d00f03d---15372382206.pdf
    • http://tdfinalists.ca/clients/43449/File/tatubibez.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160edf3ae8957b---91060936789.pdf
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/7dc5ea2ab6f597c4f8c3086c492874f2/27273344805.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bba0ea886ba---910914818.pdf
    • http://agendatourvietnam.com/hinhanh/file/93948441670.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bad9701a648---126577999.pdf
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/f9b63ca32e98e18ea7a172a91897323a/17000493564.pdf
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a9667fc32---23797129514.pdf
    • https://ruxthai.com/ckfinder/userfiles/files/jabatedi.pdf
    • http://triatlonbizuterie.cz/sites/default/files/file/46596585609.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=examen+de+segundo+grado+de+primaria+primer+bimestre+2019
    • 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_off0000c636.bin
ddbce184a6121b6dbe5e90022e9378754afe4120c7124872f2cb2944a391b8d2
pdf-font-stream PDF embedded font (sfnt) at offset 0xC636 17748 bytes
font_01_sfnt_off0000f35e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF35E 16792 bytes
font_02_sfnt_off00010b75.bin
bd02cd9eb4ed7dc36eb30bad1a81b9a4b51c7ae6f3d78703a4d968d004e3c62b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B75 11476 bytes