Malicious PDF — malware analysis report

Static analysis result for SHA-256 c2a8a8b739a48344…

MALICIOUS

PDF

72.1 KB Created: 2021-10-03 10:07:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 79278684ecb978c4502f88f2400866f9 SHA-1: d1aad74ace3ec936e04ee140d7f187442c295307 SHA-256: c2a8a8b739a48344fece6ba6a78fb1081f970ecd88618ce8cfeb68101888bef6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities and executing malicious code. The ML classifier and ClamAV detection strongly indicate maliciousness. The presence of numerous external URIs, many pointing to PDF files on distinct domains, suggests a link farm designed to host or redirect to malicious content, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://glovimex.com/uploads/ckfinder/files/jekow.pdf In PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/worexivek.pdfIn PDF document text
    • https://xn--bankkrtya-41a.hu/js/ckfinder/userfiles/files/46277852400.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/nupex.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/8a8850e33171a06407b1d0d87ed4823d/24349183711.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/dedaxobagunexede.pdfIn PDF document text
    • https://eravukappalpalli.com/userfiles/file/95134113156.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/164371bbded6eb3ecd8484601f45f280/75000227861.pdfIn PDF document text
    • http://visoda.lt/ckfinder/userfiles/files/25354719260.pdfIn PDF document text
    • http://kaie.org/userfiles/file/20210927211401.pdfIn PDF document text
    • https://basisnomor.com/contents/files/poluvurad.pdfIn PDF document text
    • http://amidoux-peintures.com/ckfinder/userfiles/files/68613482715.pdfIn PDF document text
    • https://olivermilk.vn/tctt/sites/aaa/file/82100432224.pdfIn PDF document text
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/fokeru.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/78019470623.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/20459598785.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/fovuwad.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/21052083450.pdfIn PDF document text
    • http://www.fuchingrading.com/upload/file/50585143612.pdfIn PDF document text
    • https://motty-etai-sharon.com/files/files/86306906761.pdfIn PDF document text
    • http://congluc.com/upload/files/laperakikojinexodife.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/jipigarevuxudakomej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=pdf+ppt+to+word+converterPDF 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_off0000b4a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A4 18508 bytes
SHA-256: 9f94d06a4499f0264d74afe817a40beb235657da339e7060824729c1b1507080
font_01_sfnt_off0000e3fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3FB 10300 bytes
SHA-256: 4a6acc08ae73a7e6950fc74fc2d9f1cbcafec9485000019ba58b97837b933a12
font_02_sfnt_off0000fb59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB59 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1