Malicious PDF — malware analysis report

Static analysis result for SHA-256 310c01e7a2ccdeba…

MALICIOUS

PDF

88.8 KB Created: 2021-06-17 06:04:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: f1687f81432e56ef927f86316d1c1778 SHA-1: 0a424596b701a4f67dc10fecb4248803282589a9 SHA-256: 310c01e7a2ccdeba3f14a45e4479d2d7469e607e3eae292d7f65cc58d4451b29
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to potentially malicious content. The presence of PDF-specific heuristics like 'PDF_URI' and 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the document's primary function is to host and distribute links. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing or malware distribution campaigns.

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 https://synerhu.ru/uplcv?utm_term=valorant+sens+convertor PDF link annotation
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/dadh04bdc07d13ad5m9us6o0lc/digidanarobeburugabefu.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/zenupivu.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/95b3b4fea42958688fd8c1b87c6723dd/zaguxixesenafa.pdfIn PDF document text
    • http://ankaser.com/userfiles/file/37562954174.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/loe5bnqlrthnfgsi0ud0m8rjvk/12506784267.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b26fc205b72---fidelawenesijilofox.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/nudqku2qmh0i4kdoi9k8lfbcqg/23670052738.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/j3seql63mp165q4okp79oi65ok/fukufulitoris.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad52c12e91---80022031218.pdfIn PDF document text
    • http://rsst77.ru/upload/files/xevuwegilunijim.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/25771937247.pdfIn PDF document text
    • http://controlsystemco.com/cache/fck_files/file/27094568627.pdfIn PDF document text
    • http://kadernictvo-svetlana.sk/editor_uploads/system/files/23312363597.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pifezeriwetegoxutobib.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16084cacd3f317---84764173370.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011d14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D14 4820 bytes
SHA-256: ba0c96375ca5d7881d90290a6dc8cd7c6ed186fd24728def197b8081ba0899f2
font_01_sfnt_off00012d8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D8A 12288 bytes
SHA-256: 47142fc7d74d745aa03936d7d8b53ce16ca01a7b080dd187f6ac29d0629b648e