Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3a7f957f445e76a…

MALICIOUS

PDF

86.0 KB Created: 2021-07-03 00:49:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: bf4dcc9d18c1450e3d0ccea691d7d7bb SHA-1: 9334c433e34bab7c0bcabd12caf29dbfbdd6ae79 SHA-256: c3a7f957f445e76a21d35e2591186dd07cc95abf1bd8fb9770bb041d3689a03d
66 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many pointing to compromised WordPress sites, indicating it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests this is likely for SEO manipulation or to distribute malicious content. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier clean score 0.1247

Heuristics 5

  • 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.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084bcfbd3cc0---lagipujarojegeledefor.pdf In PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/5586f08b5bdbebbf44d40609a3748085/28899722045.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/a7cfee0f10fae68c9c207a92663e8353/mesimijolot.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/f6k9sol9m39d0ijp318hrabcb1/saworinurujexobunajiwanad.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160acb2f14efb8---tutajivumovefif.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/faresakajafobimajirinar.pdfIn PDF document text
    • http://superlitefan.com/uploads/files/wusumefemokugif.pdfIn PDF document text
    • http://koslita.eu/ckfinder/userfiles/files/muxototilupewan.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b38df656e5f---97067930353.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a39e77b7b7d---36521883326.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/7828332d9787af91144bd3f82d47cc9e/rupupip.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/d50a697243700e9b43ae255c31a7082c/fepigakenasizifebenedovik.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/cb5289092e97daa9f1f585d32e367341/51843979826.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088dc772a48c---logukegunemus.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160ad28043c525---54563262225.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/0nvmf4749r8q48aaul08ivaui5/70194694221.pdfIn PDF document text
    • http://mega-stainlesssteel.com/uploads/image/files/31732941280.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083dd7b8c149---45288822093.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/74cf81da2f4d5724c264dd0c31f67b28/63923041575.pdfIn PDF document text
    • https://majubesar.org/contents//files/37512726453.pdfIn PDF document text
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/049c26d39bd19e07e0748606723da702/12998045123.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/73137585106.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608f100f9e3c9---57972602868.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160afbedc47ea0---ximurenizij.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/dikifokebapofidufuwele.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/femonuwekejazugunud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=authorization+letter+to+enroll+in+behalf+of+a+personPDF 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_off0000f8ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000110ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FF 17404 bytes
SHA-256: 6d3410c37c530939dff55a90cf874906aaa48e19136dca2eed78d3ec7a2fbfa1
font_02_sfnt_off00013ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DED 10736 bytes
SHA-256: ac3a2eeca9d3ae0be8b46d7a1a76dc1f39870732fbdfdcdc221f05622459bef5