Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b707d7cb47d3ba9…

MALICIOUS

PDF

70.8 KB Created: 2021-09-20 17:35:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 03114e5a50425f904906e9988b409b75 SHA-1: 5fc3fbae2ef80667cb2026b7a0b10244c222b776 SHA-256: 7b707d7cb47d3ba916bfdbbbb5aa1b4e223f0e265e87b6a4cee9dfd008538c34
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://kozlovka.mebel18.com/uploads/files/14034965357.pdf In PDF document text
    • http://jfe.hk/userfiles/92713513739.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/12043238782.pdfIn PDF document text
    • http://shopabrang.com/images/files/newofavezalotunutodolif.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/2f8ab082944c3401b7b05649ee968fcf/degukiwusararure.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/39147498017.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/rubotejudasavimudavuwal.pdfIn PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/mawofovu.pdfIn PDF document text
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/45074092852.pdfIn PDF document text
    • http://ibnuaffan.com/ckfinder/userfiles/files/22861685151.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/4758236236.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/5100661910.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/26315908376.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/8988667722.pdfIn PDF document text
    • http://kim-clark.ru/files/file/topugarapopekokagejuwadex.pdfIn PDF document text
    • https://klcconsulting.eu/klc/file/4391762664.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/rixetowujo.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16145542c9f2d3---muruxikanobagozesudam.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16134115c07a74---tawakevekifuxasobomiduw.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/31660156877.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16148408ed5183---benugolexivurubu.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/7931945485.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=change+theme+androidPDF 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_off0000b67c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB67C 15452 bytes
SHA-256: cb4ad660d2b9b40096b1395710676ccc4bcbf5ad5920435903935f5264f5eb62
font_01_sfnt_off0000de4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4E 10512 bytes
SHA-256: e51033640e5a6588b777f2473589202de4269cada0bfcc30f0ec1f5a8af56deb
font_02_sfnt_off0000f5d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1