Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb50283affcdccd7…

MALICIOUS

PDF

76.6 KB Created: 2021-06-18 02:57:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9c6ae26b3bc3af95d6c9320b209019b4 SHA-1: 5f92bce0a81b0543832d18d568e0c49c6244f78b SHA-256: bb50283affcdccd7a3eade0a6c0ad969e6ac108673c9f2c16152b69fd18793dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload directories and disposable hosting sites. The presence of 'utm_term=zero+city+hack+apk' in one URL suggests a lure related to hacking tools or exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://cremyco.com/app/webroot/docs/file/98074930607.pdf In PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8ed68c151---22495940710.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c409dddd42b---zekapanepuwivujosijo.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160760320b330f---kujomi.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607decabea299---59506261018.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/163da1a89a0b3350e35f10def834b0d8/47527912442.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16084268796a53---madoxibowubujis.pdfIn PDF document text
    • http://erex.hu/upload/file/sanekek.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608087101c7f9---dabefelelab.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607630435fc62---ronet.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16074d42420153---numodu.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/63d2e5a3c2ee1f46915b8965191eae82/satibumapifurav.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/1a27ff96e93108556289e6b3e9c50bf9/79911118595.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/v78fp97n0s9o52t5c6gh4islfb/pilojedeka.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/9936064309.pdfIn PDF document text
    • https://samyenngochoang.com/wp-content/plugins/super-forms/uploads/php/files/t14p0dg540ueu4cdbk8ckoksvd/gowavitupos.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=zero+city+hack+apkPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE490 4932 bytes
SHA-256: 0f1c07f36c6d10040a2c9f18ece71d63a5aef79f106b69f679fa6cecf2d2bcc2
font_01_sfnt_off0000f55a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55A 1800 bytes
SHA-256: daad3f347a4f42f432ee9983e619a7c063e36761dba5934b469418034847e28e
font_02_sfnt_off0000fde8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE8 12212 bytes
SHA-256: 36cd72b5c96cc28ba452c40964ba7a3df63f679b2e0c6c32dcffdd63f84137c3