Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3f81cd685475ad4…

MALICIOUS

PDF

76.2 KB Created: 2021-07-06 11:05:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8af05fe815b7ab0a51be39a582ef0138 SHA-1: 819acb53d9c54f49819ad389ac7074d62b3b006b SHA-256: c3f81cd685475ad45ece999fc568b6b5f0e1c6c680f3e8a7f349b440cd4d30c7
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to websites that appear to be compromised WordPress installations or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of a link farm suggests an attempt to obscure the ultimate destination or to leverage multiple compromised sites for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7328

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://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16078337d995d9---82304783018.pdf In PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210701_CC24C883E9443DF7.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160868126bb040---82678960707.pdfIn PDF document text
    • http://unicaconsultoriarh.com/images/files/karotogovamixer.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607786b5d5206---meduxibaga.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/16246039255977.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/61324328959.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d95ba968a7---30983344012.pdfIn PDF document text
    • https://anjingliar.com/contents//files/lurutikanumejiwepixumubem.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a7b1478c4---nanipojisoriwesame.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/93391185039.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa65169d68---birawexozosisutikoparix.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa22d0fe6c---47057581807.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160803a925ed65---73715259187.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/80d795a97b4746b5f0391f55826211cf/nemizesizegarano.pdfIn PDF document text
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/2106fb495f6e497c8dedfb235313936e/78200574607.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712350b4012---43038522215.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/kr2iv1cikkn7cgbdp72o63k8nl/57415913131.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/49910958926.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608abb7a9d974---28530165993.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/3q23im5k5dh5831fi9rqiotbem/41187583690.pdfIn PDF document text
    • https://ijmscr.com/ckfinder/userfiles/files/11575642744.pdfIn PDF document text
    • https://hurghadalife.net/userfiles/files/25686280717.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/68722053302.pdfIn PDF document text
    • http://prime-standard.com/piceditor/file/rodibasugofonezaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=software+testing+interview+questions+and+answers+for+2+year+experiencePDF 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_off0000f174.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF174 11556 bytes
SHA-256: 15334a6ba218db50c92a562e5edaf48a39dc98d1edf87e56de9fcecce2e1ca9a