Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb59de38d1978066…

MALICIOUS

PDF

86.0 KB Created: 2021-09-02 16:56:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8555418ccb0726ac56c9cdc90ed863ee SHA-1: d001a98e5dc52b9311046e84751c93d66e1cb2be SHA-256: eb59de38d19780669ca3d85325097c4389702fbc7a807ecc3e9df15c3dcbc5ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to compromised websites, many of which appear to be using vulnerable CMS plugins for file uploads. The presence of these links suggests an attempt to lure users to malicious sites, likely for phishing or further malware delivery. While no scripts were explicitly extracted, the nature of the URLs and the 'link farm' heuristic indicate a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6115

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://nuraski.pl/wsg/userfiles/mugogagimixofojadabetif.pdf In PDF document text
    • http://kwong-cheong.com/userfiles/fodefen.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810bbf5599c---gijeduxok.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/d647173a2919f5aba6a2d8b7ba7cbfc2/56643389393.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/56537180170.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe6f91af1f---13817469857.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c03d89f338e---41526811073.pdfIn PDF document text
    • http://atallmed.com/userfiles/files/fegabilabezekoxodiwe.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202108/file/letalatu.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/lipapebilobefowetunito.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160787f3cc33bb---xevofas.pdfIn PDF document text
    • https://resonanceacteurs.nl/userfiles/file/21863712063.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bc5af1b74cc---fofugemire.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16081914a41965---damuxezef.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/a11b372a461ddfce5da2b2603116dac4/zaxux.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdac4ce92b6---90667927534.pdfIn PDF document text
    • http://bygreenpure.com/userfiles/file/futabojekizuzuvapakuvado.pdfIn PDF document text
    • http://ansatrans.ru/admin/ckfinder/userfiles/files/nivajovuponujonugejiwafun.pdfIn PDF document text
    • https://12tiga.com/contents//files/janedumedawosat.pdfIn PDF document text
    • http://sumtinathholidays.com/admin/uploadfiles/file/kozejilepo.pdfIn PDF document text
    • http://kbo.pl/ckfinder/userfiles/files/31809050220.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/77486400560.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=mackenzie+vestibular+2018+pdfPDF link annotation
    • 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_off0000f044.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF044 18840 bytes
SHA-256: a187cc216560d606266227fc09af082e5b582d25c8eee12e149769183362baf7
font_01_sfnt_off000120e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E1 11448 bytes
SHA-256: b26c8be72e57cd3d084a77c7cb9984babb35b8f8e6825aa55588149fb0996771
font_02_sfnt_off00013c07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1