Malicious PDF — malware analysis report

Static analysis result for SHA-256 0022451b951bf58c…

MALICIOUS

PDF

69.3 KB Created: 2021-09-16 15:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 23e7a9eec49ea9e23f1c0d96862c9deb SHA-1: 1869e9dced9a7d7b8110189cbf7fce5050d0fb96 SHA-256: 0022451b951bf58ca874298f1a05f6e28f1fd101bf1f15d8250813dc1719124a
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as a malicious PDF by ClamAV, indicating it's designed to exploit vulnerabilities or trick users. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting, suggesting a link farm or phishing infrastructure. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the document's primary purpose is to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4539

Heuristics 5

  • 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
  • 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://nomylo.ru/uplcv?utm_term=mixed+present+tenses+exercises+pdf PDF link annotation
    • https://cafesca.mx/ckfinder/userfiles/files/11577263132.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/jibabesozit.pdfIn PDF document text
    • http://szamosiszerviz.hu/feltoltott/files/vorogurovexasopap.pdfIn PDF document text
    • https://otterdisplay.com/userfiles/file/bawodomevugijomexe.pdfIn PDF document text
    • http://xn--zb0by3yusal20ak5lcidnwigi.com/ckfinder/userfiles/files/1631545985.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/bf14e8775781b3633b67d4fe74232b40/22137024921.pdfIn PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/jivilixupuberovalelinubam.pdfIn PDF document text
    • http://saipanbooking.com/FileData/ckfinder/files/20210915_544F67BA653CDB44.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210902141158.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/11896529424.pdfIn PDF document text
    • http://fecirturizm.com/resimler/files/lifaj.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9d2c96c8a---sivenu.pdfIn PDF document text
    • http://sz-nuoyi.com/Upload/file/2021091519313325538.pdfIn PDF document text
    • http://eclickapps.in/userfiles/files/fuxoderomaborigu.pdfIn PDF document text
    • http://neza.cz/UserFiles/File/misurado.pdfIn PDF document text
    • https://yumasri.com/assets/ckfinder/userfiles/files/jeresadagovuzonamotitisat.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/31861931089.pdfIn PDF document text
    • http://fmafirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13318637579.pdfIn PDF document text
    • http://aorganboys.handyfriendship.com/upload/files/72899496985.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/161392b053c73d---fuwalamedamifowe.pdfIn PDF document text
    • https://estoniapools.com/contents/files/puluzefatazugajutenofel.pdfIn PDF document text
    • https://viceda.com/userfiles/file/witolopovase.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/89192963453.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/161401a2b8ed0a---49982393134.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3C5 17212 bytes
SHA-256: 977f2cdf0195a302fafc9223a88e90013eefec10a0643d98581505f64c095290
font_01_sfnt_off0000f009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF009 10380 bytes
SHA-256: 91a9041ad4122dddaca28147c10a5d9ccbcba7182be64e62721902634c326403