Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cbb3d0de02a638e…

MALICIOUS

PDF

81.8 KB Created: 2021-09-17 12:00:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bf621b9382c7ae2e88a8066bff57c826 SHA-1: e985a5d092d5e38b34b6dbbb0f3dd391c0bfef01 SHA-256: 3cbb3d0de02a638e33caa5b9d82ff21126c33385cc61c89b49fff29ded9ca6eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to external sites, many hosted on compromised CMS platforms or disposable domains. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, suggesting the document is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://crewmak.ru/uplcv?utm_term=fighting+simulator+codes PDF link annotation
    • http://gamax-motor.cz/data/dokumenty/vuwuzalexapumeri.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/zetibi.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/25368124017.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/doxigaropezasomutu.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c99937301c---39938163629.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/2530799700.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/pibewelaxopukumuvobisad.pdfIn PDF document text
    • http://hftyby.com/upload_fck/file/2021-9-10/20210910050600325019.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/53f85e6f0f4ccf449e9147b00c3806dc/88035259415.pdfIn PDF document text
    • https://tectrongim.com/uploads/files/xetavoki.pdfIn PDF document text
    • http://gamebonda.com/ckupload/files/40744264348.pdfIn PDF document text
    • http://jawarakreasi.com/file/43823899871.pdfIn PDF document text
    • https://cartolmania.it/file/64997135022.pdfIn PDF document text
    • https://www.jdconstinc.com/ckfinder/userfiles/files/24763255593.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161378041ea891---23818211771.pdfIn PDF document text
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/70515408077.pdfIn PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/fosorage.pdfIn PDF document text
    • https://littleedupark.com/ckfinder/userfiles/files/kikidafitupu.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/vumalejuge.pdfIn PDF document text
    • http://tv-kitchen.ru/files/files/31171318627.pdfIn PDF document text
    • http://imobiliariaimperio.com/files/files/98817833773.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/munexisoroxidew.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/bejuresopokusetipixe.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_off0000dcec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCEC 10896 bytes
SHA-256: 1525b6d1bf16e2ad625ebef850fdb856160f05ceb66fc984e2fa9ed95664233c
font_01_sfnt_off0000f5b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010dc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC8 17000 bytes
SHA-256: 9d35251821a4723229ff2dc778c24cd5d27b37c4edccfba11b6825b722b7da33