Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3fa0fe70b1b6f51…

MALICIOUS

PDF

88.0 KB Created: 2021-07-14 02:49:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6a4990da1aa338461088a622e1dcd368 SHA-1: 6d405097f4063de6960b119b28437ca070861181 SHA-256: a3fa0fe70b1b6f5127a612d0ccd67c8a2ab66c37c4fc6d92bad464a3c64d1ce9
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to numerous URLs, many of which are hosted on compromised CMS upload directories or disposable domains. The primary purpose appears to be directing users to external sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://usaoxin.com/userfiles/2021-6/file/jobam.pdf In PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/afc50a47f2aacdf7e66f7c7e7ccb709b/gimiragexapinadavuxi.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/0e91801a028d3ecf3a359966b808e3de/dopipedimevavav.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/wugotamomozogusibofuvibet.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/jevokikexazedomed.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/5fd37f14c4f438b5c8810590e5ebc8cf/59875087778.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160936be8355aa---29232375120.pdfIn PDF document text
    • https://avigailpekelman.com/sites/default/files/file/fagivida.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1609739f3d080d---47356918178.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/julozaluwoluxenuvot.pdfIn PDF document text
    • https://www.apollopowersystems.com/wp-content/plugins/super-forms/uploads/php/files/1de9529897d220b096f517c14ca19167/widifegibat.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc22f9df2c---mimalupemesukulisomufi.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6485e9044c3451d187648b1db60a2940/sozepulizebijewosit.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4c06d9900---73717053094.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c12a7e1ab18---zavoloxegifiwufim.pdfIn PDF document text
    • http://soflcops.com/clients/83267/File/55278152427.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/75qqnnsvsgg183kk1jc070fr57/lorufa.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/o02smoems0iergtik85eccv082/7088325248.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16085bbde95b88---biseduwonenapiroros.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a9050ec1d---92498302229.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077eac501958---18516466654.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/27870394808.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16083b95676969---92086751535.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/c7f5bd5671ddf902d36b9d2475616858/19871709922.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/49122734003.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/tmo8aonn31bj0vfnojtbee8j5p/zobuzelok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=pacific+hydrostar+1500+psi+pressure+washer+manualPDF 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_off0000f1ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1EE 17244 bytes
SHA-256: 6a7e43089e108731c4b0bcea791ab8cef26854fcc929502ae7e2229267839b74
font_01_sfnt_off00011ec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136DC 11496 bytes
SHA-256: 569d8eedb7dd1deb80b3ef90ef41de378031a4d15ac2e50270e83c7d1c39a222