Malicious PDF — malware analysis report

Static analysis result for SHA-256 c557bc3ceece6746…

MALICIOUS

PDF

75.4 KB Created: 2021-06-19 15:22:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 1728a02fa677305c01a6eea0434e6950 SHA-1: 93b04bb4a89d2082338e647a28b1ba2cf9d75f7b SHA-256: c557bc3ceece67461e91d364a74dfd66fc8673c1b4cf63edfa9c413959afb86b
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing and malware delivery campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f190200143---48692948334.pdf In PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/a4638d6fc526e379207c3219f2c0a871/sopigiris.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160977033956cf---84136277458.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/sofokelini.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/d67605140559f3533cfcb8b94b05ba9e/79895954278.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/0oq2fl87bmil2f0j7djfr42rb7/33380349385.pdfIn PDF document text
    • http://bazis-expertiza.ru/ckfinder/core/connector/php/files/xalaf.pdfIn PDF document text
    • http://www.celso.org/download/rirowelekimuva.pdfIn PDF document text
    • https://melz-feu.ru/upload/10039129268.pdfIn PDF document text
    • http://xn--80age2amlc.xn--80adxhks/pics/images/file/12885304962.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607e38f36643e---75492063141.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/4d8og7gj7hmv0k30rill3her11/bumepatupekabusepuwonul.pdfIn PDF document text
    • https://lederstuhlshop.de/ckfinder/userfiles/files/2992420934.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/khr4npdkef09q0cfnc57pqb981/49711401913.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861618e5c84---mewirogorafotif.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/a5b1c7c2680bc4d3fa5ae652bcae881c/sazuvoxubano.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/kuvokinutaragezijaveri.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/YTWXjIUwRh0/uplcv?utm_term=mission+kashmir+watch+onlinePDF 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_off0000e5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FC 5200 bytes
SHA-256: 384671dbe14753ec4fc232518d9e7fd52b071697121d8c863c515f8120f033e6
font_01_sfnt_off0000f79e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79E 11752 bytes
SHA-256: ac6a1613be5d1b7c09ec97f65ea858a144972464a7b06e686bad95242b9d6b73