Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a83710d6b5e014d…

MALICIOUS

PDF

82.1 KB Created: 2021-09-01 01:33:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9bd1ffe97ea58c0badf0ecc4444a9e6 SHA-1: 95a947418a36990cb260cb2bfaf2134441bf23c4 SHA-256: 1a83710d6b5e014de52e6cc470e08a123382260ee79bbd574aae1dcf4c5680e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to facilitate redirection or exploit vulnerabilities, hence T1059.007 is included.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://philabc.ru/uplcv?utm_term=approximation+questions+for+bank+exams+pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611c0953eb81c---82209863543.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/sfc3hekjbmncqh026qi4ele865/mafojinitekametudov.pdf
    • http://findusafranchise.com/files/files/42107949547.pdf
    • http://bjsprt.com/uploadfile/file///2021052501505696.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612d35b363d60---49318720501.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/08a00dce4d7736fb57990582ec65ef77/zedotuvekalim.pdf
    • https://parkettworld.com/upload/files/87494823795.pdf
    • https://btsis.com/upload/ckfinder/files/ruferitobowol.pdf
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/dogodunenipapuponimosidap.pdf
    • http://sea-cruise.ru/ckfinder/userfiles/files/pafupowukilu.pdf
    • http://champagne-marc-chauvet.com/images/files/42380500752.pdf
    • https://infypos.com/infyposcms/media/22676209687.pdf
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/8e12c92f9bcf033f7507261af0f75cd9/tozowozavorovarusaf.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cef913d0308---dijitime.pdf
    • https://eamenfaraz.com/cache/fck_files/file/salumopivapakodev.pdf
    • https://parc-hotel.info/file/36899409025.pdf
    • http://vikohasanfiber.com/upload/files/39887523326.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb7f50eeda---9464661692.pdf
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/20df4da2bcd246ce81b7e76ecc2f2e1d/guxifoxupavenitelusow.pdf
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a02f48f3351---wonenobusemarofoxipifanaf.pdf
    • http://tahi.hu/ckfinder/userfiles/files/27139615245.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/sg3e3s8ofoas7ua4qnkkp9r086/99508958296.pdf
    • http://contelex.it/userfiles/files/bomepalazedixemutixovizan.pdf
    • http://langfordfinancialservices.com/userfiles/files/razoroxevokojazas.pdf
    • 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_off0000d70a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD70A 16792 bytes
font_01_sfnt_off0000ef21.bin
71fb6baedc1160ff656bc87269310e2be53097bb6d918a2cd453ebd6a0c8bfdf
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF21 11176 bytes
font_02_sfnt_off000108e8.bin
83aba9ebe4389c8e03f1f70ea386fb4335b3b84ba9fa4aaad4c5becabd815b8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x108E8 18892 bytes