Malicious PDF — malware analysis report

Static analysis result for SHA-256 55d06af429b5b82f…

MALICIOUS

PDF

80.9 KB Created: 2021-09-03 22:01:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: d96d2a86108bb7e7244a3adeb7913fa2 SHA-1: dc2a4e842f4dcadd7aac08de759eaaecfca0482c SHA-256: 55d06af429b5b82f99cec8bc23618d0cf2dae73205ec512b244ad985e42dca6f
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on potentially compromised or disposable domains. The presence of numerous links, including those pointing to WordPress upload directories and using UTM parameters, suggests an attempt to disguise malicious destinations and potentially engage in SEO poisoning or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 http://lhs75.com/clients/46937/File/xegogogo.pdf In PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/2b8987a64dc46c2959084aa0fe22e006/nufejiwapulotumulojo.pdfIn PDF document text
    • https://wegofa.com/userfiles/file/sojarewivipilitededasik.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/6dit4s8320vni7flv154qmo8ig/nasasituxufasilopebodez.pdfIn PDF document text
    • https://associazionebriciole.it/public/file/rexet.pdfIn PDF document text
    • https://gmt-tw.com/app/webroot/userfiles/files/10294939121.pdfIn PDF document text
    • http://changecn.net/ckupload/files/44416678151.pdfIn PDF document text
    • https://pioneerlift.com/upfiles/editor/files/nafasud.pdfIn PDF document text
    • http://dejede.com/userfiles/file/roxezaneraja.pdfIn PDF document text
    • http://keemunblacktea.cn/uploads/file/070939082724.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2d6a5fcf0---masekixadavisexajoba.pdfIn PDF document text
    • http://aeusjtu.pretty-match.com/upload/files/saguvelali.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/21316b5f8c5e75d1e808d414ba31189c/67113792319.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/utstttr6nfl4dbntvlb1v6pi4u/19637660798.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/1539e919d909c8e382f14de6e143d28e/befeloze.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/77301604497.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcaa0752e8b---40377930292.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f51c42e0f---29743014934.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/63602931798.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/11116504815.pdfIn PDF document text
    • https://biothiennam.com/media/ftp/file/mibexegatabamuvoxorode.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/26368992007.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/rixube.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=norma+iso+13485+espa%C3%B1ol+pdfPDF link annotation
    • https://easyown.ddproperty.com/datas/files/zivewemi.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_off0000d42d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD42D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC44 11284 bytes
SHA-256: dda1274f26a5ac5883eb5a75eb15382b599ea23ff84e789b7d5ed4aed587f9e2
font_02_sfnt_off000106cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CF 17644 bytes
SHA-256: e1bc6d969e5eca868f8bce774125eeaa6926b24f936f908e1f99c33e50eb2009