Malicious PDF — malware analysis report

Static analysis result for SHA-256 321207c23ab7beb8…

MALICIOUS

PDF

80.7 KB Created: 2021-09-11 19:37:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 117323cac40a1684b1098a4661960b7b SHA-1: d6d0405280b7d941b3277955de378b99b3953e8a SHA-256: 321207c23ab7beb8ae9f726309dd5a6a635164bb08b458de21785ca0c3d3777f
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal that the PDF functions as a link farm, containing numerous external URIs, some of which point to compromised CMS upload storage. This suggests the document is designed to lure users to malicious or compromised websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://aias.pnu.ac.th/ckfinder/userfiles/files/genanuwetodajijovi.pdf In PDF document text
    • http://okmarin.ru/userfiles/file/wajom.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161354263bf5ee---93035544037.pdfIn PDF document text
    • https://5a.ro/ckfinder/userfiles/files/62834072649.pdfIn PDF document text
    • https://adesso-moosburg.de/images/file/53625781139.pdfIn PDF document text
    • https://boumqueur-edition.com/upload/fckeditor/file/32704182729.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/5fef9d105d79a88bd3b288b31d341e78/61482615702.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be041a2841---kalowenisit.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog/file/38452042122.pdfIn PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/raribituxuwevixe.pdfIn PDF document text
    • https://milsagliksen.org/upload/ckfinder/files/20828786619.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/ragor.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/30072457681.pdfIn PDF document text
    • http://www.tecnobor.com/ckfinder/userfiles/files/begegomiwi.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/31361497711.pdfIn PDF document text
    • http://siamintertrade.com/file_media/file_image/file/80966963080.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/1f7f0b828c44a084e18ab84085082279/17510692886.pdfIn PDF document text
    • https://mar3ol.com/Files/files/22348029651.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/dafakurejorupivubuvek.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/gaxiroduwawivamax.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/71175796950.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/3456501597.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/51550332180.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/ruvul.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/88325648741.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=is+103+prime+or+compositePDF 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_off0000d380.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD380 19072 bytes
SHA-256: 92079def170e5d570b1d482fa842b2922e93a16ccaec5078a3a859a3e8191664
font_01_sfnt_off00010514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10514 10520 bytes
SHA-256: 8b4c73c79f1ffab13e7fb517a4d1819dcb8153acecebc7c4f4e08c5927995988
font_02_sfnt_off00011d28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1