Malicious PDF — malware analysis report

Static analysis result for SHA-256 7351d7a8ab2f558b…

MALICIOUS

PDF

86.3 KB Created: 2021-09-14 08:19:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e9ba02d530967ae785f84beb091c7307 SHA-1: 50f1e71087076ba26d181d8d1bb7103c3e82ba4e SHA-256: 7351d7a8ab2f558b19a38d273237e3d0b267e460a44d6dd9a01f2921f406743b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to distribute malware. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161392b6aac0e6---58198011757.pdf In PDF document text
    • https://nazrabilisim.com/calisma2/files/uploads/37008991450.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/1b96no4dab3afbgsubnd5kvsa2/49412448292.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/vowevogujumupazubomuno.pdfIn PDF document text
    • http://greenvisioninternational.gm/userfiles/file/vabajapakodazobopisisure.pdfIn PDF document text
    • http://kodemari.info/data/files/kekuluvemelevuriw.pdfIn PDF document text
    • https://digireg.com/upload/58217172499.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/58074358655.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/28268606808.pdfIn PDF document text
    • http://metisentry.net/ckfinder/userfiles/files/48588224002.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/95873067872.pdfIn PDF document text
    • http://candientushinko.com/images/file/kawozuvaf.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16130cbe81d7bc---wawafitixobanitubata.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/275522757613d194d5d5c1.pdfIn PDF document text
    • http://hungbuloon.com/media/ftp/file/78690113091.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/161376b150b7f7---genatokumuj.pdfIn PDF document text
    • https://congchung7.com/upload/file/nimopafofe.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcf5a7c370---90090703276.pdfIn PDF document text
    • http://robertfeinberglaw.com/images/edit_images/file/12040871908.pdfIn PDF document text
    • http://quangphong.vn/uploads/image/files/gegerokodinifogaraza.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/70276803958.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/68938364795.pdfIn PDF document text
    • http://wolfroccatiassociati.it/userfiles/files/wubobomojabowa.pdfIn PDF document text
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles/files/77392344238.pdfIn PDF document text
    • https://anninhsieuthi.online/upload/files/77231532469.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/nasepukoferufelasa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=curriculum+definition+pdfPDF 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_off0000ee3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3B 17616 bytes
SHA-256: 264bd07b969f541a485e6ab8ba8b52000ead9f12c929756f34f74dcb30b04596
font_01_sfnt_off00011bb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000133c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133C9 10584 bytes
SHA-256: 60cc852ec384be8b196424516fb67d21688e0104b52844e683d5a8979ca56bf6