Malicious PDF — malware analysis report

Static analysis result for SHA-256 55f0f56f8c7b42c6…

MALICIOUS

PDF

81.0 KB Created: 2021-09-10 18:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 953effdd30e91530cf5155b7b4b35412 SHA-1: 9e383441bbe47ab86cd431dc99170d0561e79f79 SHA-256: 55f0f56f8c7b42c6ecfabf0ce423e7d5e1347e3d4d5115776551e230fa0af168
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting it's designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine its function as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • 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
  • 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://allytemp.ru/uplcv?utm_term=zip+code+of+caloocan+north PDF link annotation
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/55871069236.pdfIn PDF document text
    • https://divanich96.ru/admin/ckfinder/userfiles/files/jotufixukisomejuv.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/47661747495.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/48651073234.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/20310874790.pdfIn PDF document text
    • https://shindah.com/images/ckeditor_img/files/ponibobuxise.pdfIn PDF document text
    • http://isystem.hu/userfiles/file/nuxega.pdfIn PDF document text
    • https://claudiodituri.it/uploads/82634165947.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f970644160---zezomebisalogupozenoforel.pdfIn PDF document text
    • https://www.aicsmindia.org/ckfinder/userfiles/files/45766173861.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/24f5f2e2733bb15124a73f9532c383c9/28607902138.pdfIn PDF document text
    • http://www.saletime.gr/admin/fckfiles/file/woxide.pdfIn PDF document text
    • http://iiiemjobs.com/FCK_Editor_Images/files/mexufalapu.pdfIn PDF document text
    • http://okvin.org/userfiles/file/newekewutovebizuzegimuvo.pdfIn PDF document text
    • http://atdawnwelift.com/userfiles/file/64765461218.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/k7gdhgeujk1s6pqc56ghgu7480/zajupatinaferimizerefixe.pdfIn PDF document text
    • https://tuvanthietke13-5.com/webroot/img/files/19169656546.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/72572346456.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/retow.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/gadijogorilu.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/86763843270.pdfIn PDF document text
    • https://gemicilojistik.com/userfiles/upload/file/63492442463.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • 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_off0000d8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CA 17656 bytes
SHA-256: f6105e371d2b7de174d050a29204fe103f66f58e39c47fec65cd73109ab29cfc
font_02_sfnt_off00011eb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB4 10512 bytes
SHA-256: e9f1d213046b3f29c981dd1f2b014e98ad75082b347f924e4975aaaa1ab1b4e0