Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c64eb396fd1c42f…

MALICIOUS

PDF

85.0 KB Created: 2021-07-02 23:56:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 697c09369607ad8f04d551da838dfa1e SHA-1: 138f9e4786dcda283cacb408587de7919decd787 SHA-256: 6c64eb396fd1c42f6edfa8c394a5692e6db99fc179e252881dcc06c8ee86e980
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous links pointing to potentially compromised or disposable hosting. The document body is unreadable, suggesting it may contain obfuscated content or exploit code, but the primary function appears to be directing users to external, untrusted URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://newabel.com/ckfinder/userfiles/files/76528180951.pdf In PDF document text
    • http://paillasse.hu/userfiles/file/boref.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/kazajurogitufopumawunede.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/f84ci8gpm96onfcimc0ji3cmas/69956324020.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/f833fbb38acdcc959e5c00610fda0d4b/jotelikozexufomo.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/4534482205.pdfIn PDF document text
    • https://arerp.kr/data/file///bofasuxemokelifewakidivis.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/2230005280.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcfeb0ce94---xuzotiwesowez.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/tuvema.pdfIn PDF document text
    • https://people11people.gr/uploads/File/61646367020.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160703e40d54cf---15417483855.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/fbf6c08cb2d17bff84e5fb404124b8e0/7183178949.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afc91a1dbff---garumotixubegaretovukos.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/d81a9f7b9cad6039b524ff4446484c15/6556149139.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/1e6a577be330cdabc5d131cccb516894/zuvaj.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d00725408f5---gewulogo.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160987fdd34b8f---kevuno.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/o39pvjlscsknbma2dkvvvmiom5/kotudodejibuwat.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d6e9ebcefec---xuwazixanazik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=shl+answers+to+numerical+testPDF 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_off0000ea18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA18 16980 bytes
SHA-256: e7a538d15007854a6df6c7dc9de293dc6914f3600515f8f9fae320f5af3852e6
font_01_sfnt_off0001163e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E55 10756 bytes
SHA-256: a1ce2830bd883b4d2d91df65f3f0d0f6091ff6cf753c70e1a274a1e6c5f79bb2