Malicious PDF — malware analysis report

Static analysis result for SHA-256 28e728e5d2cd802a…

MALICIOUS

PDF

120.9 KB Created: 2021-07-14 05:11:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 78bf4270933dbdd4a50921f11e3340d5 SHA-1: 05c8371f6768fb0f4d9cc0a4c92a0b4511b64147 SHA-256: 28e728e5d2cd802a729189c38474f317ac5b7467aacf6be5c665e7eeca7b2028
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3270

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 http://phongkhamducphuc.net/images/files/keganomivite.pdf In PDF document text
    • https://healthmatters.me/userfiles/file/16898864073.pdfIn PDF document text
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/43070456575.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608129efd27ac---48395445705.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6f2f7c277---3030572263.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a145f976255---guwudifuleragorugi.pdfIn PDF document text
    • http://aa-nusd.jp/5896748681.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/lnkld8e0luf8lbv6qkkb4ln9j0/21276858543.pdfIn PDF document text
    • http://siembra.me/uploads/files/23610411594.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/ffb123fc0b51b744c5f78e3fe4cbee11/19590587110.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2f20af1f0---texilimezutuxe.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/cb5740ff65e47f5c191339317c7e8073/42086716991.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/50066332235.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/t9ib5avdm51i1vv3gsqkhgq3t1/pemamogidakedabekiza.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096f390485d4---pitowakafugugoz.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/kuzunox.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/2636d7df79fcb4f25083e14d44689cdb/pizopurezop.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/a975030660e5613ddc2e7843883d546d/tikinogeb.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/35948310482.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a402f138b9---63855426122.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0b298317c9---25578198976.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=squamous+cell+carcinoma+tongue+stage+2PDF 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_off00017f9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17F9A 11016 bytes
SHA-256: 82838600332f25bf15d157e8cbdd0d1e21dc963d9cdf2a5fd37e52996ad0dbe1
font_01_sfnt_off000198ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x198EA 18804 bytes
SHA-256: 2201075bc814234a5ef538c9bdc27b23371e9355c2c9fde0b5936a544f98aa26
font_02_sfnt_off0001c9e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C9E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1