Malicious PDF — malware analysis report

Static analysis result for SHA-256 355a6f331c23e97c…

MALICIOUS

PDF

80.0 KB Created: 2021-09-01 04:14:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 861f5c1d1ebf83cc637df7edf20c625a SHA-1: 8c52fce996f63353835dde9982240fdd09228ad8 SHA-256: 355a6f331c23e97c6f337ee616c4d99748d5ed5af184821d948d5dc853db204b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm with numerous URLs pointing to compromised WordPress upload directories, suggesting an attempt to distribute malicious content or conduct phishing. The presence of these links indicates a likely initial access vector via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4e35b3824---sazolediboteleralun.pdf In PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607822be6f0d8---pemijifevu.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/7694284111.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/31048766577.pdfIn PDF document text
    • http://ghhs1968.com/clients/5/57/5762190d0a265df614d1f295a7060a42/File/nolabivavawewitaxosos.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16094b92c910cf---taxunadezisudidunatamofig.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/peberutewarirokad.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/53856874123.pdfIn PDF document text
    • https://tavio.ru/files/file/kadukemopowotafej.pdfIn PDF document text
    • http://voxel-avocats.fr/uploads/file/46197006223.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/57034069247.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee4e37b24dd---49099542877.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/jizifogevekaxilaz.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/7cac8be824ed2f0b9ff117b54ba1ded7/fajazodarafikugisewimi.pdfIn PDF document text
    • http://jinohair.com/upload/files/94643007925.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad04476a6c8---41597857748.pdfIn PDF document text
    • http://vector-food.com/userfiles/file/2411072579.pdfIn PDF document text
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5b8dc5503---8719222311.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/ce14548235df4cdb9028065af0c5cb70/87852995296.pdfIn PDF document text
    • http://alptw.com/images/files/dibusamakavonanoj.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b666f06374---23567967161.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a83178d13---fufademuxasaseju.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/9b700b2b5f296e2c31e4af0d9505cfb3/19260525292.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=check+out+the+videoPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d49b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD49B 10176 bytes
SHA-256: c7af0e08b6648d39b372237132ea03949f356ade022e1c22340ad73c0663a871
font_01_sfnt_off0000eb92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB92 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A4 18028 bytes
SHA-256: 3006c55ad35fb9a660d48394044dec08830db72db4cfd3f9c0e217572e84f6bf