Malicious PDF — malware analysis report

Static analysis result for SHA-256 b03f21d0fb5be0c1…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 21:00:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 929d9ff7fa6cb3b8728d86d0011f3013 SHA-1: c505a056c5f9cc9fdc0651500a3f82eca72ffb1c SHA-256: b03f21d0fb5be0c16ce1f4a3e7cd132ef796a81fd8f53e4cd6d3b5ed5f4aedf3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs, many hosted on disposable domains or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the link farm and the PDF structure point towards an attempt to lure users to external, potentially malicious, content.

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 https://thucphamtruongxanh.com/Upload/files/93271041348.pdf In PDF document text
    • http://zespolbahamas.pl/zdjecia/file/12054904556.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9210ebe52---30107070780.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16132f73ee90db---56477757536.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/xinedavutapolonuxone.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/lifowukego.pdfIn PDF document text
    • https://tavio.ru/files/file/3530933855.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032983f5b6---20518038702.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/jorakatebul.pdfIn PDF document text
    • https://westhigienia.hu/editor_up/fufadefuxere.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/8954908396.pdfIn PDF document text
    • http://elitvorota.ru/f/file/69994652802.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210911220158.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/penenibuguvifezewof.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/4844038632.pdfIn PDF document text
    • https://globalathena.com/ckfinder/userfiles/files/siwufaj.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/jufirero.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/99974102326.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/salijejobumobovuz.pdfIn PDF document text
    • http://zatuchlina.cz/upload/file/94829856242.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=best+virtual+androidPDF 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_off0000d83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD83A 10460 bytes
SHA-256: 120c0d7bd3023c20f4ab08756447e998aa03b87d2bd2cef7999042d6d12a1da6
font_01_sfnt_off0000f022.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF022 17592 bytes
SHA-256: 1b27311d0a450ab739fd89ac21e2077e43169a9424098a44a15ce40fcee7e41c
font_02_sfnt_off00011e03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1