Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c3d098c3f2f518b…

MALICIOUS

PDF

72.3 KB Created: 2021-09-21 03:37:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 78c17485db7081d83a43d23db8e10ab5 SHA-1: f2431fcf0d657afab0ec1f2cc9972f004e545a24 SHA-256: 6c3d098c3f2f518b1c76802c1e1375c59b25fafbb367fdf5ad74276aaae2cf85
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various websites, many of which appear to be hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of link farms on disposable or compromised hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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://himalayanespresso.com/espresso_ckfinder/userfiles/files/95786508782.pdf In PDF document text
    • http://kahasat.cz/data/file/20784827945.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161375c09b2a2c---8612077521.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/0mfu4ea7m5o60o3oossemk82q6/kazudex.pdfIn PDF document text
    • http://ehoron21.mn/uploads/files/13527848947.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133a4e4713e2---51552861817.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109201702311563.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/161300cb909b43---94554254819.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/rupapasevexejo.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/taxisatubidudoxirinesu.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/likevuxumikawobenu.pdfIn PDF document text
    • http://iknow.pl/files/file/sofupewukajudorajisut.pdfIn PDF document text
    • https://kvzriu.org/images/file/lijebidi.pdfIn PDF document text
    • https://butagallery.com/userfiles/files/fabitotamufenewasofevafu.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/5039011532.pdfIn PDF document text
    • https://seo-methodes.com/userfiles/file/gudelonujomerilunaka.pdfIn PDF document text
    • http://kmbb.at/userfiles/file/mewaguke.pdfIn PDF document text
    • http://lamekatus.ee/uploads/ckeditor/files/jodabajosi.pdfIn PDF document text
    • http://onlinevay.com/upload/files/91577967591.pdfIn PDF document text
    • http://steakclubhn.com/campannas/file/79393487812.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210921045711.pdfIn PDF document text
    • http://xageunion.com/userfiles/file/jabadize.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/kaginap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=wireless+file+transfer+mobile+to+pcPDF link annotation
    • 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_off0000b882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB882 16508 bytes
SHA-256: 1307857d7c76e2f19f36a82a4e51d8c918aeca51009760b86b7708820a4267ee
font_01_sfnt_off0000e314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE314 10772 bytes
SHA-256: b2ba15a896c82238327bea2b5e5a723671581c06ad15489e52c4efbd8204b82c
font_02_sfnt_off0000fbac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1