Malicious PDF — malware analysis report

Static analysis result for SHA-256 5822aeb50abb337d…

MALICIOUS

PDF

74.0 KB Created: 2021-06-20 09:10:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: c6761604d5ea0cb23a45c29a8141143e SHA-1: 89071f131773e24d36e71ce78aeb3f926b7cb6a3 SHA-256: 5822aeb50abb337d87ee15ef252a119b929b9bfd4cc044ef93136ecfd07a73ff
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites, suggesting a link farm or redirection mechanism. The document body, though heavily obfuscated, indicates it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the lure-based attack pattern.

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://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607cbb3f47fad---nesuraxuvogop.pdf In PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e8003c9b1---dibaguvajodit.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d5502affb---7952817846.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/om2kgesn1booeaffn079e4gs78/zaferiluj.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/74215486726.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b58731a30cb---66365602927.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5c81e3075---29272019339.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/sevopuginij.pdfIn PDF document text
    • http://atek-ent.com/upload/file/sirodinewo.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/p8p7nisna7hci44vpjgo66l3ag/fimowalote.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/2klcenefap9anm301hf5jmbo50/bexoxajojogoj.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/814h3imic18dnu4o0krbt59tb7/42362639858.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/xojajafixe.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/nemuvekorobefuz.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/5a20931a3131943c6e30e57a84f7ae62/34744268885.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/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=military+drum+cadence+sheet+musicPDF 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_off0000e336.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE336 5284 bytes
SHA-256: f1f0cd67c9a0839ba3dd396b57d6928eec2d3a64a167d41ef2b60516cb94ebfd
font_01_sfnt_off0000f512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF512 11244 bytes
SHA-256: 5e8bae1ef79e9046b0327227f9d31e076452f55b0ef6526bef7bb7b8c139ccda