Malicious PDF — malware analysis report

Static analysis result for SHA-256 458b431933d52779…

MALICIOUS

PDF

84.3 KB Created: 2021-09-18 09:15:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3a7ffc8d7a3afb0656de0b2808efce16 SHA-1: cdfcda16752fb45e87ecb98b3d6a1242b6e38967 SHA-256: 458b431933d527794858a389d08ddec8cd7eab3478a88ed1e329948390101cfd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with several pointing to compromised CMS upload directories, indicating a potential phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of a link farm on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://bamor.org/userfiles/file/49601542836.pdf In PDF document text
    • http://fanghsin.com/uploads/files/202109140417597030.pdfIn PDF document text
    • https://md-bud.pl/szklo/photos/file/52531662195.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/kekajowuxisopuwajesuri.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/jezomuzor.pdfIn PDF document text
    • http://drivingtesttips.ie/fckeditor/userfiles/file/67667555404.pdfIn PDF document text
    • http://nceed.kr/pds/userfiles/files/74722565884.pdfIn PDF document text
    • https://strongpointmarketing.net/userfiles/file/lilaxuvelazoluropobizafe.pdfIn PDF document text
    • https://karpzbeldowa.pl/uploads/userfiles/files/rizixasamu.pdfIn PDF document text
    • http://diakmelo.hu/ckfinder/userfiles/files/kapibulofo.pdfIn PDF document text
    • http://teleinwestor.pl/userfiles/file/71846428491.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614211ee890ae---wejame.pdfIn PDF document text
    • http://land89.com/ckupload/files/wovagesupurirotu.pdfIn PDF document text
    • http://architettosbaffo.com/userfiles/files/92775853035.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16138da22177bc---41374418312.pdfIn PDF document text
    • https://flavio-tonon.it/public/file/65883261996.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/e2vcrh9h132fvur1jg09hnlsk4/mafadazaxadinogav.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/biwijevifegir.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/80805266498.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/9011252b57a36f1f413eaabe82f32eca/pojelulizidoboxuvikipofu.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318eaea054f---tumufuwibaf.pdfIn PDF document text
    • https://asmitahrgroup.com/ckfinder/userfiles/files/77136901902.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210915_163443.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/29829481800.pdfIn PDF document text
    • http://ccadl.com/files/20210917200111.pdfIn PDF document text
    • https://feldmann.pl/userfiles/file/58171419908.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=grammarly+mod+apkPDF 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_off0000e4d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fced.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCED 10204 bytes
SHA-256: 6d91e8bfd4f7e4050d9a9284655226de6b4254ad0fcc76333b303d7ed0bd85c8
font_02_sfnt_off000113cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113CC 18384 bytes
SHA-256: e0e2a5aaf7e9fda510f1e7a9b04072ce8bd7246c9f33478ba8cafbb1a31f5cb5