Malicious PDF — malware analysis report

Static analysis result for SHA-256 4355792a25162f2e…

MALICIOUS

PDF

179.1 KB Created: 2021-07-29 15:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 802ea8833a3096c26a2a10dff21727e0 SHA-1: 448cf42c21eb9960b0479cb544e04b867a21bed2 SHA-256: 4355792a25162f2e97e25bd1e4ac33b312bb6253c17028830ccd52e60451e0e6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and other domains, many of which host other PDF files. This structure suggests the document is designed to act as a link farm, likely to distribute phishing content or further malware. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9284

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098475c1bba6---30757125861.pdf In PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/298dbf93d9716ecdcede01e4cd09e69c/38500676199.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/62344994205.pdfIn PDF document text
    • http://internationalnetworksolutions.net/files/In PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160cb3ab387a16---5912157748.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/vugawunizu.pdfIn PDF document text
    • https://actorconseil.com/files/file/mewogez.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/6cl7fgm25qev69cnb10ug6bsma/81732478255.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/52925900313.pdfIn PDF document text
    • https://angelsforwarriors.org/userfiles/files/25029957217.pdfIn PDF document text
    • http://stl-hk.net/userfiles/51558888878.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/tuvudev.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d7fc9107917---10666062248.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/kilum.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082f45cbe924---wukukunivebufegaxiruj.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/dimes.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/96134811491.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c4148ad6153---12070933339.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210529_E403D35C373DCE66.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/e76131dece1568f5c08ba1cfa359fb26/38334159052.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/1v99ifkcs6kbsi1amksgnctub3/41433846050.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b24377b9ce---pijakoluj.pdfIn PDF document text
    • https://mednet.mk/public_html/upload/userfiles/file/wesikojukobanunano.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/e7e9ab204219f4e78a5b81a2a8178c30/fofozajefizilaferus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+do+you+do+intercompany+reconciliationPDF link annotation
    • 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_off00026d0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x26D0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0002851d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2851D 17196 bytes
SHA-256: 79c85b5dc142007e9ba702ecdab7425d367ea68c4ed7c1109754ca2e1de7ed57
font_02_sfnt_off0002b232.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2B232 10800 bytes
SHA-256: cbb1fef3ec96a28c6e8b6f28163258cb607e0d6613590fa242c487e10d3b58b4