Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc6554d1a1ca0131…

MALICIOUS

PDF

83.7 KB Created: 2021-09-05 15:32:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: edffd1c14cf3764bb88814466e8d4ed4 SHA-1: f6484fcbbc329fd093f588cb5178756f26895314 SHA-256: dc6554d1a1ca01313eb9ac98ac3e7a1d7d5dbcb48dc703483a40530195ed9987
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to distribute further malicious content. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware delivery campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://clickkedai.com/userfiles/file/repowijijef.pdf In PDF document text
    • http://dellalontra.it/userfiles/files/xojizufawakedudaj.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/93808416071.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160f5cd4a1eead---48073359347.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160d73472eac7a---82839472207.pdfIn PDF document text
    • http://iltorg.ru/upload/file/16676699403.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/vizosukomo.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16100b68cef153---46669009099.pdfIn PDF document text
    • https://olterus.com/contents//files/widekasedope.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/fe559130533c3c49a908b6f952796e1d/kegelelininigozoj.pdfIn PDF document text
    • https://summit-christian-academy.org/scauserfiles/files/27828219405.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/loguzoboravimodokifowaja.pdfIn PDF document text
    • http://nanumed.ro/uploads/files/momewakitif.pdfIn PDF document text
    • http://dtpokebar.com/uploads/files/xogogoweruxezusa.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b71432b3fa1---fevaxizugotube.pdfIn PDF document text
    • https://parokisantolukas.org/Uploads/userfiles/files/62467231237.pdfIn PDF document text
    • https://nevisnews.com/userfiles/vofisifire.pdfIn PDF document text
    • http://szpk.hu/_user/file/dudaj.pdfIn PDF document text
    • http://rghsalumni.com/clients/82979/File/xajomesojalonar.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/5d3338ac639699fb0500834e67ff6f06/47382321105.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1610bfaedb96ae---7947759991.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/95531637425.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/xoxagokovawenukavekafa.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/wimupujufisebesepopig.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=t%C3%BCrk%C3%A7e+s%C3%B6zc%C3%BCkte+anlam+sorular%C4%B1+pdfPDF 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_off0000ddd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD7 11552 bytes
SHA-256: f4afcb8c2d5e1945f3f03241293b258c1f754c721a1a54cec779a82371885af6
font_01_sfnt_off0000f82a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF82A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001103c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1103C 19360 bytes
SHA-256: 72f9858b879319bd7a14c9a674cadb3ce1e59a382ace5f60b5043ea0efbc633d