Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c5c2b43c3028f97…

MALICIOUS

PDF

72.2 KB Created: 2021-09-08 16:50:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5113bf689e3979115be0294acc315b0b SHA-1: 870f3e78528f67a5137072d17815bcbdb5b0f372 SHA-256: 6c5c2b43c3028f976f9ec5192a37a80abc7eb72f3b189ec52b2b0720e77e4618
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised websites and disposable hosting, indicative of a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://philabc.ru/uplcv?utm_term=oxford+discover+2+grammar+pdf PDF link annotation
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/161304ce5e5447---70600160051.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/a42638e32dfd5361dce04c791c68e7a2/37074184370.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/saxavedamame.pdfIn PDF document text
    • https://mertlakustika.cz/images/pages/file/baxukexifik.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/77258706637.pdfIn PDF document text
    • http://coimbrasoftware.hu/images/uploads/files/kivedenitumawun.pdfIn PDF document text
    • http://sibzakon.ru/ckfinder/userfiles/files/zotix.pdfIn PDF document text
    • http://pscemetery.com/userfiles/file/85005557001.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/81390049526.pdfIn PDF document text
    • https://medpressa.ru/files/file/xajigipixedid.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/0h6g5vrudtfjnpt3stpps0dko7/67896597452.pdfIn PDF document text
    • https://nulifeus.com/~nulife/userfiles/file/59013507465.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/47407070913.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/vosotipuvobibikato.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/zozogizemamipijikireni.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090819483312.pdfIn PDF document text
    • http://104408017.linker.tw/files/fubituxu.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/1025711699.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/fajajifimetosebos.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/wetirepamarumed.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/6586a3edcba3a269319ea4ba37172431/fogefosemizim.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/fimarapazivojazagi.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb47a93480---zuwumonosejorufibi.pdfIn PDF document text
    • 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_off0000b861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB861 11028 bytes
SHA-256: a97480ca7ac244b1c6280fcb85a5642cb73c7e6c9d75e9e37f17fec4e2cb48ed
font_01_sfnt_off0000d1f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F5 16136 bytes
SHA-256: 3f127663c7a3a293894f7f68e06dd98f063ad79f1b4dfca0e138dd7ade8ccf20
font_02_sfnt_off0000fb5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB5B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1