Malicious PDF — malware analysis report

Static analysis result for SHA-256 afef858fb01d0080…

MALICIOUS

PDF

79.4 KB Created: 2021-09-08 12:00:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 39810af71e80ddc33d88327c4ded5b31 SHA-1: 940e8639f2489fffd1dc9c248d4cc50da2611e5a SHA-256: afef858fb01d0080d89298b85318aab8492e022084eb20f13925a51d6e785f36
156 Risk Score

Malware Insights

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

The PDF was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL patterns suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://asustainable.com/global/file/4977855437.pdf In PDF document text
    • http://ricoconsultingattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/40372413919.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/328295925d3f1b04d43a114f288e6568/nixofonawetogizabapu.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dulebawumiwefiserix.pdfIn PDF document text
    • http://coffee33.ru/archive/file/10670719725.pdfIn PDF document text
    • http://goddesshair.net/upload/users/files/59728270942.pdfIn PDF document text
    • https://questyme.com/userfiles/file/78315505034.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/72359f0de67c490cad771e92b05078b8/61008763815.pdfIn PDF document text
    • https://barcelona-health.com/files/galeria/files/nojagulazeminomisovikobax.pdfIn PDF document text
    • http://kbo.pl/ckfinder/userfiles/files/devanikutowozu.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160e375dd23be5---rovinukepenifilokomofegon.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/14449263466.pdfIn PDF document text
    • http://goneviaggi.com/themes/userfiles//files/64591325381.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/kebatawaj.pdfIn PDF document text
    • https://rjpexport.com/files/85385319109.pdfIn PDF document text
    • http://greenplanetnepal.com/userfiles/file/xojelovonekosigi.pdfIn PDF document text
    • http://fu-xin.tw/uploads//files/202108031608348810.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/00d4d5742f298ecb0df2086e95b7dec5/bevitoperoz.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607c144cc2865---66805271577.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/dageliko.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/28866826082.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/97eba71158806595a5e0cb1e4136fce1/36118432420.pdfIn PDF document text
    • https://inprovitvenezuela.com/ckfinder/userfiles/files/risixitusojabidifazegufes.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/161149186039df---wexiwibusox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=porous+materials+pdfPDF 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_off0000d437.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD437 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4E 10656 bytes
SHA-256: 83370a94cae987b664fcfdbab0f1ad413454e4a7eae7569ddbd813a38686623d
font_02_sfnt_off000104c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C4 16936 bytes
SHA-256: 00a47ddeb4d6d49a635f136ac3cbd698085a3421386c6e761ad5678277ba3026