Malicious PDF — malware analysis report

Static analysis result for SHA-256 b86d31d1c701d7dd…

MALICIOUS

PDF

73.4 KB Created: 2021-06-22 13:15:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 7a500a99f5bfc20ebf2fc9c010783edd SHA-1: 8be352e1f1c2ffc6a6056dd43e6dc758ed7dc51c SHA-256: b86d31d1c701d7dd7a653fc423ce9ab57dbba914edf96db8184a431989531934
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users. The document body, though heavily obfuscated, contains keywords related to 'porn audio stories' and application metadata, indicating a lure to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://sindonis.com/userfiles/file/zixeve.pdf In PDF document text
    • http://myafmc.com/clients/a/a5/a51d49d85de18111a3d718c63a5e5081/File/35860466076.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/tpabnjcqlpkfq5dak7q356gd5h/safatukutidosebav.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/71021220405.pdfIn PDF document text
    • http://energo-winstal.pl/userfiles/file/sojojajamoraza.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/pugenijewewugotopanuvo.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/xapurolokasovol.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080de53b70d9---rajitotulixat.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1137a49fd---90459974460.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609bdc491e81d---40669977853.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a95fab75096---22207689593.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c130948db---samibagadixokubenuvurizaj.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609d110d0db0d---bukokuwojemalen.pdfIn PDF document text
    • https://avenue102.com/uploads/file/pazoxofofunora.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841bbe95863---pemip.pdfIn PDF document text
    • http://christopherdallo.com/file/62014469864.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=porn+audio+storiesPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE341 4788 bytes
SHA-256: a4d6e19c580516552d5e6a90fa88e7bdbf8e244c7b6851521c7cd7cb8302e3e2
font_01_sfnt_off0000f393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF393 10948 bytes
SHA-256: 91905a1b42b2f1501bf92f253a5b53c73940c90f2643bb31c462838daa86daa5