Malicious PDF — malware analysis report

Static analysis result for SHA-256 c38e2b9f85a8a5e9…

MALICIOUS

PDF

70.9 KB Created: 2021-10-03 10:54:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 1f9a7363d91aec8e1ef074aca02c088a SHA-1: f91257302f9b38e07b580f062c9bb5ac19477a29 SHA-256: c38e2b9f85a8a5e9a95cd08ae2c65f073489db2d85d2be50b8011dca2331acec
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to potentially compromised or disposable hosting. Heuristics indicate this is a link farm designed to direct users to external sites, consistent with phishing or malware distribution tactics. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://queure.ru/uplcv?utm_term=reading+comprehension+exercise+primary+3 PDF link annotation
    • http://xn--80aer5aza.xn--19-kmcm3c.xn--p1ai/ckfinder/userfiles/files/28676908611.pdfIn PDF document text
    • http://uzmansporzeminkaplama.com/resimler/files/zadatolekapan.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/ludesase.pdfIn PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/duvup.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffaedf2fee---1332184607.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/midebi.pdfIn PDF document text
    • http://espwireless.net/uploads/file/nalifu.pdfIn PDF document text
    • https://juvelyrikoscentras.lt/Files/file/lebiwadimowalopisoxol.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/86186330382.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/tilenipirazadobofuvikamuf.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/62653481255.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146d21f1df5d---rudiwuxudinab.pdfIn PDF document text
    • http://studioiulianella.it/userfiles/files/wozijimega.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/29074595377.pdfIn PDF document text
    • http://sivam.pl/files/file/gimexogepuk.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/a4e017093f8de3006eb715df8cf7c819/subomarexin.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210928054553.pdfIn PDF document text
    • http://partiaweb.ir/upload/files/63409799621.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/14666330311.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/c9a69f0c8480f9173114f48ebf3f358a/78910853941.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a12a480638---vaxeluwojetujiteme.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/91164611505.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/9958970340.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/53871742006.pdfIn PDF document text
    • https://debden.org/userfiles/file/In PDF document text
    • http://sladkiy-ostrov.ru/userfiles/files/17755585399.pdfIn PDF document text
    • 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_off0000b24f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24F 16044 bytes
SHA-256: dcab55d6cf51cd30c9314c6a99c5d3480a742a38bf8622cd6be20ff1a0b2543b
font_01_sfnt_off0000db81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF398 11248 bytes
SHA-256: bdca82c603fede30a9afd27847e6e745a0389f87b6f22f1ca418ee0de27d6267