Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4df7ecf1fe82cd3…

MALICIOUS

PDF

64.6 KB Created: 2021-09-10 11:32:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5d3d134bfcfa1353f40d2cffc5757b95 SHA-1: 63f22c947785c8c1f3c9032d68d451c9bb726d0e SHA-256: a4df7ecf1fe82cd301fe796a30d2cd3fc99c77cfbb74c989d1a571dc3875df08
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and ML classifiers, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The presence of numerous embedded URLs, many of which are unknown or point to potentially disposable hosting, strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5692

Heuristics 5

  • 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
  • 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://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16135ed276b1eb---54116558843.pdf In PDF document text
    • https://taumed.kz/upload/2021/09files/210901042454271265erzu1.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/ladajurivojekaj.pdfIn PDF document text
    • http://rayhovietnam.vn/upload/files/wasiwizomujenovob.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/jasuxidaw.pdfIn PDF document text
    • https://wisestudentz.com/userfiles/file/miwulovek.pdfIn PDF document text
    • http://vetcasatenovo.it/userfiles/files/lofodokexun.pdfIn PDF document text
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/pivuginafuxirelunigedew.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/f0e73ef10b17431d49f41a39d1defda2/21983684442.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109041356124870.pdfIn PDF document text
    • http://ballarioarchitetti.eu/userfiles/files/jikevosi.pdfIn PDF document text
    • http://thenikharvconsultancy.com/userfiles/file/46544216649.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/51840950208.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/buxadus.pdfIn PDF document text
    • http://opersan.com/file/71444704376.pdfIn PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/54005737611.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/talike.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9ab1a182e---86163901200.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/f3db0110c61aae8ef0b4bdef182b7ac1/sumumowamuponap.pdfIn PDF document text
    • http://gr-chem.com/upload/files/28578688657.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/27640794124.pdfIn PDF document text
    • https://hgb.se/filer/file/488989611.pdfIn PDF document text
    • http://megalaserasia.com/upload///84813335631.pdfIn PDF document text
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/80097469967.pdfIn PDF document text
    • http://scsytech.com/upload/files/sadofokurolefapofoxasu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=emulador+de+android+virtualboxPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/1ffd4fe1d1e98cc142cc15360e417dfe/4050731271.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d52f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD52F 17356 bytes
SHA-256: 3ddd79fc275c3e2c7ce308636e8f543546832c508c45e22e8295a7da7722e3ed