Malicious PDF — malware analysis report

Static analysis result for SHA-256 67db5c389f4f038f…

MALICIOUS

PDF

68.9 KB Created: 2021-05-01 23:13:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 21a51b037a844224bc274ce950e11087 SHA-1: d8a11d4c773564e92c3368ed377235a382dbf56b SHA-256: 67db5c389f4f038f123b2cc8e37cb5b329ae3cda54e17eb598888651cee7868f
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of embedded URLs and the nature of the heuristics strongly indicate an attempt to lure victims to external resources, likely for phishing or further malware delivery.

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 http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0a390f1b4---39222061988.pdf In PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/ec8c7f68d9ac1cacdd661596d2a8111c/wurebuk.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16085778b09ec9---97476260682.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/b5273816a4df0ce5a037c7aef0e18d03/rosukamurapo.pdfIn PDF document text
    • https://contabil-fiscal.ro/mm/file/dawuzoxogu.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/21635626435.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607757bb752eb---77743915041.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/4a12731d33d8270446f4c015ba50fa4b/69793615573.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/b98b9aac80948512af9c159737b09644/88981263914.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf1014e697---78627564948.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160728e1b6e922---duwugokilatexiwabimo.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607979e453017---37036629438.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f804948f2---dokon.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7f12bdb44---78190539614.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/S30rS-6n6vg/uplcv?utm_term=architecture+informatique+en+%25C3%25A9toilePDF 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_off0000ceb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEB8 5200 bytes
SHA-256: 172d438600ef623c695990a63fd27b42a58f5ffa9c7655725cf60b64e1045356
font_01_sfnt_off0000dffb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFB 12156 bytes
SHA-256: 644930da471530ce036c47b57a79a5159d49739c1a6799efebd9ab88ba9da228