Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d3f1cfa96545833…

MALICIOUS

PDF

71.6 KB Created: 2021-09-15 16:12:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5632812f5fcdaeadb9ab3136e0c3a29a SHA-1: 713f54a7e8fa5e821bdb563fea349da42176d85d SHA-256: 7d3f1cfa96545833ac520fbdd849282ff0c0a5482b7d3eeb5724505610d6f2b3
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting. This suggests the document is designed as a link farm, likely for SEO poisoning or to redirect users to malicious sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://hum-lucknow.org/test/fckeditor/file/zobepozux.pdf In PDF document text
    • https://juraganmonyet.com/contents/files/tilad.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/18409985743.pdfIn PDF document text
    • http://savalis.ru/userfiles/file/84799863293.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613172052e450---kejuletilad.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac7cf73c6c---73357048787.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/nasux.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/9dbab4771f8019c09dcf470dd0e485b2/76057663468.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b7ed88cd9---71530983042.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-01-08-36-47-41.pdfIn PDF document text
    • http://artio.pl/files/files/zaniteto.pdfIn PDF document text
    • http://boek.se/bilder_umeny/File/nibifosopijogawom.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/12714961691.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/wofopa.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/35028585209.pdfIn PDF document text
    • http://logiccpacma.com/ckfinder/userfiles/files/5518775643.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/55733050494.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/fegaxijevavusomavok.pdfIn PDF document text
    • http://mabifitness.it/userfiles/files/feguresizedilatagepimimo.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/c46bc88b0cb847a56dd3c584421d1c8e/36719839020.pdfIn PDF document text
    • https://stotex.rs/files/62591951613.pdfIn PDF document text
    • https://adikmanis.com/contents/files/wodoxotonox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=360+root+apk+english+version+latestPDF 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_off0000b53c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB53C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD53 11052 bytes
SHA-256: 620cf4f0e04373afe7a9a115abe4b9bbffdfbedb290270986a3a5b82cd03d1d4
font_02_sfnt_off0000e6fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FC 16208 bytes
SHA-256: da3127eb3d95fd2e9286a2abb4d0e08191714ea41d6d5bb3880b724f9ccdb1ab