Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcf5852c0acc8342…

MALICIOUS

PDF

68.9 KB Created: 2021-06-06 22:23:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 10b358ed1428497b7db0fa7ab07cc66a SHA-1: 9ecaebc40853a78341075dbb2bbe7475f7dabc6d SHA-256: dcf5852c0acc834229f78c493c92a606b732d7001697eb89f0cee21c521a791b
156 Risk Score

Malware Insights

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

The sample was detected as a phishing trojan by ClamAV and flagged by an ML classifier. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution campaign. The document body, though heavily obfuscated, appears to be a lure related to an exam guide, aligning with common phishing tactics.

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://wastran.ru/uplcv?utm_term=guia+del+examen+ceneval+2020 PDF link annotation
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/58850bde7742c7d1012497362da55040/72563272823.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/d72f5feba5295415ba41150794837eb2/17265418468.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d7ce831f9---fupazuboref.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/280258192581.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/tajizeroguxelib.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/v2840lc0ugcpbkg0v9gusmc6u2/4512322648.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a416c397a7---mejunekasunisirawopew.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/43401962554.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/vetima.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160838be05ce8e---14122602275.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/a6efa57efdc07c79b67c35e7d9c18a88/77784308641.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/0cbfc33d27a2808d9f88c6e2b1345779/puruniwojo.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/pewusuxeno.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a750b27dc---temafunikanemowen.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160ab27153faad---jefusederugijezozep.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/636bc7c94fee3ef1cf45c01f406d72a4/3518206448.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/3a8aa7bf941e08de3c44285a3a25eb30/pidel.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off0000c569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC569 5244 bytes
SHA-256: 8fc9bf84d1f9fabcab857a024ee77d2c0f165f9f8d2e424075117d6f0623e2d4
font_01_sfnt_off0000d73c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD73C 2044 bytes
SHA-256: f56b0298392e275c109a0b32a541ca4ea7103d2c833af441416bc0960d073f4b
font_02_sfnt_off0000e015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE015 11456 bytes
SHA-256: 4e43e664fde165e915679afd5481e44791c7f6d9b3fe3ef2436900c29ca7e9cb