Malicious PDF — malware analysis report

Static analysis result for SHA-256 511fb6d360a05bde…

MALICIOUS

PDF

74.5 KB Created: 2021-09-05 13:30:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 001ac707782219f4574d682e3dd8ee5f SHA-1: 1976ab18087ff3cb47d8909b4ac5fe330cb7d603 SHA-256: 511fb6d360a05bde711919be7295bbda47292bea30d4e9dc47b8e6ffaaf5b466
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to compromised CMS upload directories. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous external links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://voxel-avocats.fr/uploads/file/sapavidimopelomenisaves.pdf In PDF document text
    • https://soechi.id/userfiles/file/pifaregafu.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/91a94t9hrfp44h4dvpstg2l374/89781559161.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf955b0ff7---74771518196.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1610f007b10691---gikukisomimeregazemixefot.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160965b37a6de9---jakenenipuzuxikitasa.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/161097aeee3e85---12748733873.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/14912695605.pdfIn PDF document text
    • http://appli-veolia.net/ckfinder/userfiles/files/26659941011.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/8ovo6chjje8gdm94sant8ske6f/5858218979.pdfIn PDF document text
    • https://promenade-perpignan.com/userfiles/file/wifuvo.pdfIn PDF document text
    • https://onlinendttraining.net/files/nivujufikosenisubu.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/edd3a9de0ac7336a63845be3de717da6/71254149239.pdfIn PDF document text
    • https://defaico.com/d/files/98182579477.pdfIn PDF document text
    • http://sensor4you.com/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202108/file/remir.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16083d0be7799f---makejufubisajaxanolodali.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=parkinson+pdf+tratamientoPDF link annotation
    • 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_off0000bf67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF67 10708 bytes
SHA-256: 344dc855e9407d9ce0efa22c71c2f52d650200f5871db60a63e5055e8f938d58
font_01_sfnt_off0000d7f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7F6 17464 bytes
SHA-256: 4c92b25bc4806c41f34cc218b1fc4a68ac9845c1760ac37fd01e924405698b26
font_02_sfnt_off000104fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1