Malicious PDF — malware analysis report

Static analysis result for SHA-256 308785fcd14db34a…

MALICIOUS

PDF

74.4 KB Created: 2021-09-01 14:21:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6f4b05db5f751cfc652cacbff494a468 SHA-1: 09a3828f35688798ce37e0cb50a88f0c787d4c08 SHA-256: 308785fcd14db34adf66be543ef2ec567c4df39b5831446b6009dbff94ec2ec3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the heuristic firings and URL analysis point to a common tactic of using compromised sites to host malicious payloads or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://medvor.ru/uplcv?utm_term=background+of+photography PDF link annotation
    • http://stensoproject.com/userfiles/files/gavutimilumexalanori.pdfIn PDF document text
    • http://joyerialaplaza.com/ckfinder/userfiles/files/65490276724.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a64ee38676b---62829637586.pdfIn PDF document text
    • https://mbzgogo.xyz/web/img/podborky/files/71478075759.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/70059422639.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/9346061287.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e8cf733f8a---68280198721.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/4d558d7367c72fcf57dfe917930da856/25371815528.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/fcitjdiplrb2dgnh9aqc7o0qs8/10670579843.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e6852ed46---funubapapalesirixo.pdfIn PDF document text
    • http://www.tsahimmongol.com/uploads/images/files/33035068146.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a1611ca20---parubezinat.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/rikafituwebijasujujelarik.pdfIn PDF document text
    • http://spamsmsgiare.com/media/ftp/file/27666146650.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/17107554691.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/49qinqlcfehpn527rh08l3fg7k/46625182101.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/ffaf85d39a2113a26f4deb3ae079fa76/96257675053.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/8da2jsh1qb42raokpsrtaadn73/sijose.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_off0000c180.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC180 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d997.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD997 10820 bytes
SHA-256: 1f2ded9beb8a99c533e1f5db7ff7ef6e5e951b84f898d0d1c1c7335f65900ef7
font_02_sfnt_off0000f25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25A 16300 bytes
SHA-256: af5dc5c3a9818fc6e0581aa12fc3afe398ebad1966530bb0f90bab86a367d41a