Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc735b4165cc15c7…

MALICIOUS

PDF

77.2 KB Created: 2021-07-20 00:09:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: d4c33f996452eb61d867ae39be40eb51 SHA-1: 881bab75b9689386c346f9ee89dbe5fafe1e8d1e SHA-256: cc735b4165cc15c757d54f0f51cc2d7f74c539514ff5ac1e0a84a07bc7f0dfd2
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, and it contains numerous embedded URLs. Several heuristics indicate it functions as a link farm, pointing to compromised CMS uploads, with many distinct hosts. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7449

Heuristics 5

  • 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
  • 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.isgs.org/wp-content/plugins/super-forms/uploads/php/files/2608b40ac72264dcd65673d56f396790/wubiwasuzipu.pdf In PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/2ec45c7e0eafeaf23b61cb80ec1e890a/8970454896.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/447f9bd53f91e3eb53735d7330e8ce0d/wepubijarivowul.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/zugag.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160afbb25448ba---lasuduluwuraverafaza.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/c101a95307c759fa28a3f185cf16dd7e/84578537165.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/0e628bb6524cd505207ed4ba7ec09815/31800941316.pdfIn PDF document text
    • http://technocom.pl/editor/file/fogoxeresogemez.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/0c174767185b89f60056a655790cc471/90484304795.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec8d20af1d---84678849902.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/a3dddfc8d015cdbab797d3f44fdf6195/zosudod.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/jerotozefe.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/72704229166.pdfIn PDF document text
    • http://phongthuyphatloc.com/luutru/files/bewuz.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/53414a5955947eef2b731f42de684b37/tekufozejowedetijovevusam.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/81689993829.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c45cf1d081d---narivibutapa.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/zovedazi.pdfIn PDF document text
    • http://studiophotosfashion.it/userfiles/files/80407339003.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/kimogow.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6faab12e32---ganeruxobunawemubuvo.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a174570b3d2---kiroxanoxew.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f961a5cd41---35438603623.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/2f6d6dac279deb8085ca36e8ebbcd9e6/fopikulegaki.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/513d5b013c8cf93a94ebbc6befff885b/20460522266.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=vocabulary+workshop+level+a+unit+8+completing+the+sentencePDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010106.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10106 16900 bytes
SHA-256: 801b3cd97ea64e51fa2427be6c4378a88077d7bd43f75254996a4e2cf53e14d1