Malicious PDF — malware analysis report

Static analysis result for SHA-256 91630ba3ddb1eae5…

MALICIOUS

PDF

92.7 KB Created: 2021-10-16 08:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a9f74099b66ab1734b4abdfe5e2aecb0 SHA-1: 77d7c8ce03748a8995e366a8c4ed00c3f7c543cb SHA-256: 91630ba3ddb1eae5837e0b02fd4820014fc354b8c3620b619cec0f97262f0b79
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites and other disposable hosting. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to lure users to potentially malicious content. No scripts were extracted, but the overall pattern is consistent with a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://www.clc-engineering.com/siteuploads/editorimg/file/josapakefobu.pdf In PDF document text
    • https://cooperadora.grupocreartel.com/documentos/archivos/52275494352.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16169002b5c5ca---xipirasutudedinure.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/dd2b9d835ccb2a33cf946ba2a1c211a8/3846968356.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/9249697948.pdfIn PDF document text
    • http://airserbia2009.vs.rs/multimedia/file/27720604606.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/1be988fc0fd1c85d581ad86cfefb415a/19863057549.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/fovizipovi.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/81945895322.pdfIn PDF document text
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/sujonimejuwijipunofi.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/86823784444.pdfIn PDF document text
    • https://tjpapigroup3.com/contents/files/88260397426.pdfIn PDF document text
    • http://vaonhaphatphap.com/images/uploads/files/ruvimem.pdfIn PDF document text
    • http://kmjjt.com/uploadfiles/file/041306165088.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614e30aa5ec4e---rulazurotebutakusobov.pdfIn PDF document text
    • http://polkovnik.su/upload/file/jiwukifokaweli.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614b2c5e455c8---33508393486.pdfIn PDF document text
    • http://jcsh.bluezp.com/ckfinder/userfiles/files/judevogos.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/djib31f7cd84jbo843igp9a4u7/wovufakebuna.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/dc58cb3203bb05aeb63efbbfa346317d/2705813419.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/tedenefur.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16169c6c031389---sojozafizosom.pdfIn PDF document text
    • https://oglethorpeclub.org/~oglethor/UserFiles/file/60759945900.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/47268620227.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/TSvcnjQ06Jg/uplcv?utm_term=what+is+a+marketing+approachPDF link annotation
    • https://www.posluh.hr/ckfinder/userfiles/files/mibesapofexererozif.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_off000105b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B9 10860 bytes
SHA-256: 39ec7a5f765884b9d65a0f80c38d0c5d5ee534c4553eba7aee2b53708589a7af
font_01_sfnt_off00011eac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136BE 18636 bytes
SHA-256: 0c903c44e751b01da63d18215d2237ee386a3c52bcf51c81676dc6d2f0c2b384