Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5677a97d6533c13…

MALICIOUS

PDF

76.1 KB Created: 2021-09-16 01:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: edded30a50cdfaf97f6a31c956b85539 SHA-1: cf2597fdffbfd07428986c177200dd53ffaf9cdd SHA-256: f5677a97d6533c13ffbd5ec239f94b94dbbfda9d4b9a0a0df60eabfbd1691d6b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the URLs and the PDF structure align with techniques used to deliver secondary payloads or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://queure.ru/uplcv?utm_term=best+streaming+movies+apps PDF link annotation
    • https://nicklason.se/ckfinder/userfiles/files/70655594281.pdfIn PDF document text
    • http://recviem.ru/img/upload/fewanu.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139414c5d2dd---34010474095.pdfIn PDF document text
    • http://besteva.com/upload/files/worokamovubaradudijomobog.pdfIn PDF document text
    • https://vilus.cz/userfiles/file/20619536095.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/gepovajubewuv.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/mafolofinevufulogobigedif.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/semebizozupukumanofipiw.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/fapatavaputapikabipe.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/f9eaf942ac25f03b0cceecdb2603a223/63276057451.pdfIn PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ditutiva.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fda31beac8---14324263193.pdfIn PDF document text
    • http://vecsecity.info/editor_up/motaka.pdfIn PDF document text
    • https://talenthunt.biz/userfiles/file/zakovegufojiba.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ed7a05792---10474999141.pdfIn PDF document text
    • https://adikmanis.com/contents/files/18333477380.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/goxudomivaporosozumanikil.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210909_F9926F739AABC05D.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/tabibadapovoxosu.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210903_185323.pdfIn PDF document text
    • http://budaikepkeret.hu/uploads/file/48090875629.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/migugemolamixebat.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_off0000c5ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE03 10668 bytes
SHA-256: 1ebedd0fe7692fee49f89d33d14b97d7a1d96ec20b257bf039afb36594432d10
font_02_sfnt_off0000f688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF688 17116 bytes
SHA-256: 8c6aaaa61ef06e22cfa59b9550ad8acd4e0a4de7641bf6c4817396ccdd0cac02