Malicious PDF — malware analysis report

Static analysis result for SHA-256 794d27a40d94a70c…

MALICIOUS

PDF

75.3 KB Created: 2021-06-10 04:30:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 5d7f72505a050f4d7ed3ef131c10be1a SHA-1: 9c0db5c5e8445a89e20cf5b80c6cbd84845d224c SHA-256: 794d27a40d94a70cb92de1db2a24031363e464509829e11dca1d6105fe449a57
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external URLs, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded URLs point towards an attempt to exploit users through deceptive links, likely as a first stage for further infection.

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://queure.ru/uplcv?utm_term=klb+chemistry+book+3+notes+pdf PDF link annotation
    • http://greenplanetnepal.com/userfiles/file/46185131232.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/ca6aed79390798d2e1bb7159be09cb9e/donanugedubowojukesinon.pdfIn PDF document text
    • http://petersonspann.com/clients/3/32/32c4b2f41fa698b5b938e848169c8dcb/File/46177326819.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071942dc643b---fexideluw.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16083d3002cac5---kaxer.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/82696212978.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/buvasewakatuzudul.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858a3b7baeb---gusolaxino.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/mixam.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ec625c918---satozanolusojitivowoxeb.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc0d473d087---wuxomuziledobenolazufa.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/cd8d3b8e64cc12383412619e06fb708c/32692416409.pdfIn PDF document text
    • https://monuments-msk.ru/wp-content/plugins/super-forms/uploads/php/files/581c76cd87a1dbc9acd6fd7724242a4a/56184018263.pdfIn PDF document text
    • http://navigator-33.ru/media/file/lomera.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b317ec596ec---79448165502.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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_off0000df6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6E 5412 bytes
SHA-256: 27a79c18fb4cfe584a5a2c854fb6120c8df43fe4716e24b2e42a97abaf54c385
font_01_sfnt_off0000f1a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A5 9476 bytes
SHA-256: c8eb381ecfc6ee91d7fcd8521a38e3279c6ac0dc7168507ca32055c3819518c0
font_02_sfnt_off000111f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F4 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c