Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0bd0517f8fcc88d…

MALICIOUS

PDF

91.1 KB Created: 2021-06-18 18:10:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 23e890a64b01f8eeba743b4d7e585bf9 SHA-1: 1767af192f573c7198f624a8ed0821e77d1ab6ee SHA-256: a0bd0517f8fcc88db65a43e7db755cc4fc3ba25d47d7d2485b498a038987a934
156 Risk Score

Malware Insights

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

The PDF 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 multiple compromised WordPress upload directories and other domains. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, suggesting it may have been generated by a tool for creating malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad90090fe4c---defasizilafajotagonafep.pdf In PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03213ecf51---pasawiga.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160773248e2dd5---tijezeju.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdb4fb75e4---fisomitufabox.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/59638910909.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a752353e24---jirefunete.pdfIn PDF document text
    • http://reunionclass.com/clients/7469/File/jamapowofotosoko.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aae1396e676---54568174185.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/6o6hs9vequsdlr2b720tvmhbq3/69704771598.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/16093271ca0801---36576626458.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b0f958e386a---12640983920.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d14d4c213---vapalesib.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/1de802661fb66d164e8825387339c8d2/kopukoxopopibimik.pdfIn PDF document text
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/2i2pdereoonau5absng3p3uht4/62417383758.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/9f843fb917ea5d452f092fbad966f3d9/47782243915.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/1653c4691233c770daa5a545fa34bc09/wenutovipiwa.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080cce79a3ec---20449898686.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=best+action+games+for+ppssppPDF 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://scripts.sil.org/OFLIn 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_off00011126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11126 5352 bytes
SHA-256: 75b4f5ea8c6c19144146d7290bd2704bd14f5f96ffd6b00a918c2f7750ea0b86
font_01_sfnt_off0001234e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1234E 11440 bytes
SHA-256: 1b3a23b253e1641be7b153445ccea471feb0734571a00ae711d7d698dd63de41
font_02_sfnt_off000149e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149E8 16204 bytes
SHA-256: a95eff378c135b1ab40d10b3cd1da1bafbc07f86005f57898d079c90d712ddbd