Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb96f9643103f9f4…

MALICIOUS

PDF

69.6 KB Created: 2021-09-29 08:50:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 98ae661a13e717ab27c1938b2fe0966b SHA-1: 4d9abc9b5177c86f8c4002d1c6b1ceed61f87e41 SHA-256: cb96f9643103f9f426bff561e485c3c4ba1328ec98caa2ada30001891edde5d7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm potentially leading to further compromise. Although no scripts were explicitly extracted, the nature of the embedded URLs suggests an attempt to lure users to malicious content, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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 http://thesnowmanicecream.com/ckfinder/userfiles/files/pebiputodi.pdf In PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/zajaroxekagiwudubenajoze.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/tolemilulipimafejo.pdfIn PDF document text
    • http://kammerchor-lindau.com/file/badaboboxubavelozujewa.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614240cf781b3---75689976077.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/20635668135.pdfIn PDF document text
    • http://baoveantam.org/upload/files/fimemagejofadafepi.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/midakudidokibowunaw.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/4397233753.pdfIn PDF document text
    • https://amoslodge10.org/ckfinder/userfiles/files/74106577225.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/53692002120.pdfIn PDF document text
    • https://dabanbep.tanglehadong.com/upload/files/vujulolesesorirano.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/tiwofetal.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16152c51402aa8---timiwiluvuvuvis.pdfIn PDF document text
    • http://angelascanu.it/uploads/file/26439717589.pdfIn PDF document text
    • https://valkexclusief.reviewz.eu/app/webroot/files/userfiles/files/63645971405.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/15271559299.pdfIn PDF document text
    • http://mcutech.net/files/godulaxokidev.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16138aa8d70bf4---94007056187.pdfIn PDF document text
    • https://senarathgroup.lk/assets/media/file/vubogejuvepuvasozinefopi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=cinema+apk+without+adsPDF 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_off0000aed1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAED1 16192 bytes
SHA-256: f6d0a44e60581e3b9b60b6432b8b039783b0a3137b0408874bca1773faef178b
font_01_sfnt_off0000d823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD823 10820 bytes
SHA-256: 4371a8871ca0aed940b3337326155e10890d71b5d0abd8d338b325099781bc28
font_02_sfnt_off0000f0fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1