Malicious PDF — malware analysis report

Static analysis result for SHA-256 58180b8b54737f2e…

MALICIOUS

PDF

74.9 KB Created: 2021-09-19 08:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3861c95f29c91a61f4c8df567273d251 SHA-1: e1fbd5c124708c7230c9f4ca84446a054238bb7e SHA-256: 58180b8b54737f2e3ce09342a23c11eabdf842749fee09a81cfc333c29cef1f7
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The embedded URLs and the PDF's structure suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://catamma.ru/uplcv?utm_term=english+file+intermediate+student%27s+book+answer+key+pdf
    • http://lianbang123.com/uploads/files/202109150557505893.pdf
    • http://photou.cc/ckfinder/userfiles/files/33335189797.pdf
    • http://longruiglass.com/ckfinder/userfiles/files/20210901_221746.pdf
    • http://linkingpeople.info/userfiles/file/fisajeb.pdf
    • https://ryokanclub.com/FileData/ckfinder/files/20210909_CB7E1BA3DD101605.pdf
    • http://pensionpoint.cz/userfiles/files/4744959748.pdf
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/kenisudutukusofoje.pdf
    • http://fd-health.com/upload/ckeditor/files/vasakejuzogof.pdf
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210913220124.pdf
    • https://larustt.com/upload/ckfinder/files/dedat.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/baf26293ac8e60dbd3ba7344d36a8d47/dobizutoxujeduzewaguvufo.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/d1df18157e396c41efd1290cea5a3257/mutaxu.pdf
    • http://gniortho.com/files/Upload/file/gumew.pdf
    • https://jocafoto.com/fotos/file/lozovezijoxopomu.pdf
    • https://cribpointonline.org/cribpointonline/userimages/file/24758311299.pdf
    • http://nbc.ua/design/pic/file/setidadatotirufewubutu.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161439c9fbb34e---24528554623.pdf
    • http://el-master.ru/userfiles/file/76812196322.pdf
    • http://nm-union.ru/ckfinder/userfiles/files/2763167489.pdf
    • http://razzledazzleevents.in/userfiles/file/sokefomokigevodepuw.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbcc69ed57---4730425230.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141f89778450---newalobedewi.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c10c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC10C 16792 bytes
font_01_sfnt_off0000d923.bin
ad0cab05fa966284e69d4891e6f44a06b6f1f0c6850ab2d49d776556fce87be6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD923 11496 bytes
font_02_sfnt_off0000f3c8.bin
06ac5010fbff6a6edf99f17c54d14b025c782ea71055e76d89fb1fa6f38d06c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C8 16392 bytes