Malicious PDF — malware analysis report

Static analysis result for SHA-256 b81357095002be92…

MALICIOUS

PDF

92.5 KB Created: 2021-07-27 13:52:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2f68992f778481bd95f0f292d4f3d7c0 SHA-1: 8957debabe65ca05cc78c29bbc33e0c33899d82d SHA-256: b81357095002be92d5f28f540359730f917f72ca3c218e000274b9a4779e5b45
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or malware distribution attempt. It functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple links to WordPress upload directories and the use of 'utm_term' parameters suggest an effort to manipulate search engine results for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://zcapitalcrm.com/app/webroot/uploads/files/gageduzuzawasegufomu.pdf In PDF document text
    • https://people11people.gr/uploads/File/tagef.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16095055a84d3e---wenuvureruburuzeluzuv.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d2627cf1e---18851249247.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/160737c5448b76---26633113702.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160738fa4abab1---80999206672.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/vmkgkn7ci32nvqpa2hlcokg5o5/sinojetibelezeku.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/14963577773.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1609b84bb37cc3---78285818406.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/noxozafo.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/9824271166d08b4a1ffdaa75eaa29b8c/fiwudojaxovolinalikuduj.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/gifepelugaridajaka.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/kukuvafujedajogi.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2a8975f2a---42674255795.pdfIn PDF document text
    • http://greenplanetnepal.com/userfiles/file/49511097770.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/luxufilinekijalununefaved.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/10772725060.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/gexeselowilede.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/e89ecf8fd9f261d0ecad8f5421561e8a/xamijakiwibika.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/xiwifelekezuwuvij.pdfIn PDF document text
    • http://theettiaresmontreal.com/clients/f/f0/f03dfc1790708d0b03c48e9879ef2ea6/File/wiwugikixe.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/pehorjj46idbbomk2470kv2s67/dokinogakofiwujefetep.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/f88030bc76680e35bdfef8ebbaccdd7e/90724753557.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/wepujelanopetalokadu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=best+short+stories+pdf+free+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_off000106dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106DD 16716 bytes
SHA-256: 5ffe4ccaf7364f8048f1760800b1da91a39e2edea3d7e76033e51c4a2a1866b8
font_01_sfnt_off0001325f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1325F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014a76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A76 10732 bytes
SHA-256: 9962844d930c6da950a922eb8c2fd341fa42d297ec538ce0909479abd3afcf4b