Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f7815435e51ce46…

MALICIOUS

PDF

76.8 KB Created: 2021-09-17 05:01:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a53b70fc6cad26bd70d6834cfbab34ac SHA-1: 475e9f00d4f13087f59042a9718863f22bbd9f7d SHA-256: 1f7815435e51ce463e28440d7eec45e6a5c473ad725ce72ce57e8364df75ee5b
96 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. The primary purpose appears to be directing users to external sites, potentially for SEO manipulation or to host further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://nomylo.ru/uplcv?utm_term=gta+vice+city+download+for+android+with+cheats+highly+compressed PDF link annotation
    • https://ispartaprefabrik.com/ckfinder/upload/files/xozosiwun.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/70535781396.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109140550525492.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/60732222538.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613256edae977---muboxafarifojisad.pdfIn PDF document text
    • https://ohcsi.com/ckfinder/userfiles/files/70150527550.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/74309083834.pdfIn PDF document text
    • http://hwayoung.kr/upfile/files/8762083726.pdfIn PDF document text
    • https://lomasdelaweb.com/userfiles/2008.09/file/bafuxorifu.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/konirexidofe.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/fawodezolejabexopi.pdfIn PDF document text
    • http://stroykap.com/application/views/stroykap/userfiles/file/sijekopigemus.pdfIn PDF document text
    • http://52963566.com/upload/file/202109030305362435.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/wanugeradojomukalajorob.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021090602204373499.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/121c420ccc07dcfb123b77a2ff11d3e2/35346414234.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/9ec658ceb79bc40ad1072a784921fdaf/laxinotidugurujajiduli.pdfIn PDF document text
    • http://sportservistocik.cz/UserFiles/File/57134772139.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/dfa6a8321206e1cd017dbf7f9d2600d2/navej.pdfIn PDF document text
    • http://ebonit.light.bg/includes/libs/ckfinder/userfiles/files/jaxinataseguvamejif.pdfIn PDF document text
    • https://9ja-bet.com/userfiles/file/komegakewupivi.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/puxomilivuxujuzotunigik.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/pifilunuvopezisinopunuj.pdfIn PDF document text
    • http://www.forteks.com.br/admin/ckeditor/ckfinder/userfiles/Images/83408759207.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_off0000c7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7A2 16596 bytes
SHA-256: 3a3fbb5a439a51e0fd2402e5935e188e91bea475fb019a82aaf37f16767230a3
font_01_sfnt_off0000f27d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF27D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A94 11372 bytes
SHA-256: cfd9a79984df6f5b82254e1b921106e4860494203a68cdfabcdec678aea543d3