Malicious PDF — malware analysis report

Static analysis result for SHA-256 3311d5407cd49bad…

MALICIOUS

PDF

69.8 KB Created: 2021-05-24 11:35:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: e8b0b013ec8285ff98ec073187ee492b SHA-1: eca1836c8f2470b72eabc4e04363e1a9978206ce SHA-256: 3311d5407cd49badacf7a86d77464b83f219f0871d7f8f9bdf4758ea8f58fb5a
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. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories and other potentially malicious sites. The document body is heavily obfuscated and appears to be junk data, but the presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a clear intent to redirect users to external, untrusted content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1607a75452dba0---93479049350.pdf In PDF document text
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/36b2f6c2c5b6dada504bf9f3cf5d01ed/pemibopujepufexad.pdfIn PDF document text
    • http://libertyquad72.fr/userfiles/file/94191172994.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3a2b06e1b---rivop.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/49887321726.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ad0b4cc60---dexuwepoxesibiruzopatokaj.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607fefeb70b53---xonabagedofipoluw.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7bcaa124a---86715822192.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/11308964372.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ec0ba56a6---96444034539.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160963c3b02b1c---74211671491.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160846297ece8b---puxepipub.pdfIn PDF document text
    • https://aedwea.com/upload/foto/77130757813.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16078138087074---18876123479.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/e51d61bfcd996a7e61bef7f2520fccc4/vubokanat.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/86607cc38b09c0f79b5a2bd89be1b2ac/kawedada.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/DOqCt-cVA4I/uplcv?utm_term=how+to+get+all+5+stars+in+super+mario+bros+wii+uPDF 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_off0000d443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD443 5456 bytes
SHA-256: d609d9f47024d2ae8ee505d6c78237b722f6d9184089e9bf5b6144e7b9ae7a2c
font_01_sfnt_off0000e6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CE 10328 bytes
SHA-256: 0c3a2b8ca123bf9fcada8b3623b3aab6e84cb9ba9f0b38c49e72fbf0ff5fe52e