Malicious PDF — malware analysis report

Static analysis result for SHA-256 437fe791817b731b…

MALICIOUS

PDF

64.4 KB Created: 2021-06-23 21:57:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: d0d2175cd0b5ba028a3b97f142a0d6f4 SHA-1: 06435669f52bfa0cffc4e1b0f163473a90c16f3d SHA-256: 437fe791817b731bed6d3db7483f9a8c5f6b817bca9f25b07f523682614f73c1
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16099e3dd9905e---79888288506.pdf In PDF document text
    • http://tribo.kz/userfiles/File/jinuruxawapikafizo.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/10ca01805809b7f4e176fb481fbd381b/46677997770.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/mtp6olq2gdc12mu5u7pmnf55g0/bonatufovirupomoraminodi.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8cac8c875---71568062029.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/a20ou5eh9sg395pmrlk40nsh55/64454069878.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/af1d913211d2918560d8e975736a826a/simunazejoson.pdfIn PDF document text
    • https://cutandcolorparrucchieri.it/file/nuwagevuwokib.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa592eb149---lapekamu.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d14558077b---77042060676.pdfIn PDF document text
    • http://sergey-yushkov.com/pict/file/40122431278.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/5c1ee1159e5c01d24327133306c91983/24728606157.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcdc0e5ec38---94536652860.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/66f13dc09ce155215860d6bb5401ae34/fizuzem.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/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=swami+vivekananda+books+pdf+in+englishPDF 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_off0000ba32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA32 5816 bytes
SHA-256: e80eaafa8af1a78d305511daed6e16e2c07ebfd30f99a275046659bc8cb5d39f
font_01_sfnt_off0000cdeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDEB 11440 bytes
SHA-256: cba05c005e6567351cc8e3e298ea0e56374931cb13e6210d07a984ab7a9339eb