Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cca46e3b1bb2ee6…

MALICIOUS

PDF

72.4 KB Created: 2021-09-15 16:23:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: a3da48fcac24c77e17335586775754f7 SHA-1: b79906af599c317d22e75a5093ab19ddeb7457e8 SHA-256: 3cca46e3b1bb2ee6832f8f3e054f3b3ab293d1242ca1d0cd9601e317e1bb7520
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by a ML classifier and ClamAV, flagging it as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to various websites, some of which are hosted on compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://dungcubepgiangtrinh.com/webroot/img/files/93953814147.pdf In PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/febomev.pdfIn PDF document text
    • http://studiotecnicodambra.eu/userfiles/files/pemolex.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16135bb6612845---tivigetizataxirotibapaxi.pdfIn PDF document text
    • https://pelletier-tp.fr/ckfinder/userfiles/files/buxetoxoduguzulasar.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/zawijorinumewekazejufep.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374b0d43bb9---4796049911.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/rakobitepafumova.pdfIn PDF document text
    • http://upasamed.org/Content/uploads/files/17834440135.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141e4fdc9442---21350475418.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/10866003681.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/10574622426.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/dokukewo.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/fesupizekuz.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/jogewagusov.pdfIn PDF document text
    • https://sleepthai.com/piceditor/file/73674857592.pdfIn PDF document text
    • https://www.padanguparduotuve.lt/ckfinder/userfiles/files/93554360441.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/17892597758.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/zufiwus.pdfIn PDF document text
    • http://hysansam.com/fckeditor/userfiles/image/35373994530.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/c3870f0592ba46e1cac0ee174fcdc7e7/39716751806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=3+letter+words+starting+with+k+for+kindergartenPDF 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_off0000b646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB646 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE58 17240 bytes
SHA-256: 80c511b4176efdbbe4477e87ee00d308b3a33fb5a0c71f0493ff3b4024d6f6c1
font_02_sfnt_off0000fb7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB7A 10888 bytes
SHA-256: 8e53919d5942050e23648328fbc8d1b7b87b695f7c703a35d5958cf58910f5e1