Malicious PDF — malware analysis report

Static analysis result for SHA-256 866c4859b112e9db…

MALICIOUS

PDF

83.5 KB Created: 2021-09-20 05:28:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6b4ce9581ce1dfe7fb82f5c79f398161 SHA-1: 39337cd62f934352990f5bfa2b105320e461ad1c SHA-256: 866c4859b112e9db7e59e113466b271ad840dee1040998b05c0417ca94638913
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of embedded URLs, many of which are associated with link farms and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=rule+1+48+laws+of+power PDF link annotation
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/95113138604.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/75730171088.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/mugiguvofafo.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210904_958837A4C5B8EBAA.pdfIn PDF document text
    • https://mahae.hu/files/files/gijazadu.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/1102528670.pdfIn PDF document text
    • http://ntouioc.ntou.edu.tw/ckfinder/userfiles/files/kixabutolenap.pdfIn PDF document text
    • http://cctsw.net/whly/up_files/FCK/file/20210905_094903_200.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/jojopareroruwikagusukegi.pdfIn PDF document text
    • https://morganmethod.com/ci/userfiles/files/mawatusujure.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/69411f8e8274b90b1564932c9f1c2116/21918050414.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210912222429595907h84guc31uhsz.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161462f6f8a0c8---45581551299.pdfIn PDF document text
    • https://pratham.one/file/fesuwudanomofa.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210911_9716BADF409B4879.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/zunavipe.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/2812176376.pdfIn PDF document text
    • http://bibliotekaludwin.pl/img/upload/files/41490467929.pdfIn PDF document text
    • https://grandiosieventinuziali.it/filesUploads/file/mutumebet.pdfIn PDF document text
    • http://vertracapital.com/uploads/files/tilezupupipome.pdfIn PDF document text
    • https://luminex.pl/upload/file/52035944476.pdfIn PDF document text
    • http://harnettcountyhba.com/userfiles/file/jonenabebofadiduruvaw.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/9262980123.pdfIn PDF document text
    • https://nurea.se/currency/userfiles/file/51151740230.pdfIn PDF document text
    • https://calprin.com/ckfinder/userfiles/files/begoz.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_off0000e1e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F3 17620 bytes
SHA-256: 32e525e57dc83703489a23a167f1bce860e89e0c49b28106c7937be72bf4230d
font_02_sfnt_off00012783.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12783 10628 bytes
SHA-256: 1263cbc10a6b9d8a9f2c5d43ae437d20b5f34c5a8a6e991c99c5801ffb87c4b5