Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb356e0261537e1a…

MALICIOUS

PDF

84.3 KB Created: 2021-08-22 02:52:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a22c1f1a768346c24f5a3bb444409082 SHA-1: e265426b693b44095a1a987940b133dd80f1479d SHA-256: cb356e0261537e1ad0138af095ef6228108dd4afe5fffc9a8adffb050a0d261f
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to direct users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct textual clues.

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://doktor-okonski.pl/uploadimg/file/82463288726.pdf In PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/nj83t56qadpm5aqhnref77rm71/bawebobilajako.pdfIn PDF document text
    • https://susta.vn/userfiles/file/10264641780.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609489d286741---jawisenojebodonabisoxuka.pdfIn PDF document text
    • http://montazerangroup.com/uploader/file/xovuzidobigidupijad.pdfIn PDF document text
    • http://becucci.it/userfiles/files/85004840291.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/japoxujoduwa.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/mepolenevagawuxalet.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087370aee77b---62451907055.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/68133009876.pdfIn PDF document text
    • http://agriturismolionsfarm.it/userfiles/files/buzajimudorujopufofabu.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/3meslabrpu8du9rvt10bsrc512/38681427644.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/labid.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/zasovukifilozezobejijuju.pdfIn PDF document text
    • http://xiaohecollege.com/d/files/362479052.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/jabined.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d68c2ce2c44---69847601028.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/4615f4be3dff4c85c83bdb230f0fb934/5769398904.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/muxupoma.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/34300190913.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/817e8c16ecdbebb13879e65e609446d9/gevewexu.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/e85d3014aacc2ec8ad18611f8268bd3c/98323952586.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/e38e6cfa82097dcbca85a730223cacb9/tuweletuxobugagefoka.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/b9bf8baaed7479360e0f815a447e2b98/neruwiruwiketupevuvabapaj.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/dedeliluvobozabu.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc24b00437---80922123510.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=define+diaphoresis+medical+terminologyPDF 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_off0000e32f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE32F 11184 bytes
SHA-256: 10cf2a27ad9ee20d7d8c76ad985002412ba3bbe66b6b1fafb6c2f4e20faef4bb
font_01_sfnt_off0000fcf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF8 17752 bytes
SHA-256: d1f6152c367debcdf10eecfd6bad27037d00105e53ea671e86e4be1e97cc3849
font_02_sfnt_off00012ad8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AD8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1