Malicious PDF — malware analysis report

Static analysis result for SHA-256 18c4da03e08166cc…

MALICIOUS

PDF

73.0 KB Created: 2021-06-07 19:41:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 09fae1ddc8c7e7d499179ac55dd4ed00 SHA-1: 4300eb84989afc99f947b5f0e0265bbb3b378ece SHA-256: 18c4da03e08166cceb29fc0c4d546cc16ff5979e9e0e52af3339f0eda0f125c6
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://nomylo.ru/uplcv?utm_term=can+you+remove+drm+from+kindle+books
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/09qvkg9p7u8ovi2aepd6irjdq1/83677396190.pdf
    • http://www.alexgis.com/siteuploads/editorimg/file/53658486707.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d77ea4568---389721628.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a2dd457e71a---19733183079.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160af83fbf3c05---47633895646.pdf
    • http://renovfab-menuiserie.com/userfiles/file/83166141212.pdf
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/709746580586c34bdee40d7ad2f33689/61629810126.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080a42184538---62274418452.pdf
    • https://vijyaiprismcrm.com/userfiles/files/60978035246.pdf
    • http://www.scsi.coop/wp-content/plugins/super-forms/uploads/php/files/c959e82806074e2797a1fd5224e3238a/53428364930.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085fcf24dc7a---1390071905.pdf
    • http://poltinik.ru/userfiles/file/61692058366.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/9a7b6d42a01642187b94b7236e45a611/38389569760.pdf
    • https://agrilaui.com/userfiles/file/8657526524.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/8b48327175892cb2eb92cca83905b833/zakujemixajawugupo.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/m85lbb441ru0d08bntm90165gq/50379000338.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d2dc.bin
dc716182f8a14b2477347bd4c1c3381c16f47c54bdbb45428c82658cc9a507fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2DC 5244 bytes
font_01_sfnt_off0000e49f.bin
48bd092caa42f2cff7e42b48594fc27c0f5f377d54c91309a5b0cfae7605aa3a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE49F 10692 bytes
font_02_sfnt_off000108f8.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x108F8 4324 bytes