Malicious PDF — malware analysis report

Static analysis result for SHA-256 25c7df1b0fcb3941…

MALICIOUS

PDF

81.5 KB Created: 2021-06-25 03:27:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 525e1c25da14c0d1cf642cb5d7aff08f SHA-1: 38bff9b02738528e6a295e597cb557e46a92822a SHA-256: 25c7df1b0fcb3941eccc44fd32ca2157085d41f459c341105ab1759a9a3a580e
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160928cc4dc971---62252474331.pdf In PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/26792062706.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/3rpvfpv2c6ttbbt4kcd9gl0j0g/nopitaxufu.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f333998838---bogifoganowipigoxebuz.pdfIn PDF document text
    • http://weberstellen.ch/userfiles/file/80768856542.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/86235219306.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/1523722297.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/42209754230.pdfIn PDF document text
    • https://catbasailing.com/upload/fck/file/xukaguzeze.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/6pmm0m5ui7pvs5quqib8c148pd/befogosebevamubixakebunaf.pdfIn PDF document text
    • https://proxus.nl/file/34955904288.pdfIn PDF document text
    • http://nakatka.com/files/file/xujelonosusazisup.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a182265a6ac---1302337857.pdfIn PDF document text
    • http://ramenzoni.eu/userfiles/files/75594722167.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/53cd98582f32b0dc3dc6620f5be798c9/37538222144.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606f52b547300---nabekepupi.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094589c0a8c2---53000499185.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=dwg+viewer+to+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC5 4624 bytes
SHA-256: 8487ea62d26a240ae61f711bb4f60af49a3363e114b712dbefa48d18cd230025
font_01_sfnt_off0000ffb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB3 12588 bytes
SHA-256: c212b49f7cf4ffddb5deec15162d80d1969c1cc6f4076b314abcbdae47633766
font_02_sfnt_off00012948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12948 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c