Malicious PDF — malware analysis report

Static analysis result for SHA-256 233f67e67502b839…

MALICIOUS

PDF

70.9 KB Created: 2021-09-20 00:50:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 27cdc9895d1ac4bef2fb178524953fdb SHA-1: 099f19dd7d5e876eaac7653d5293042cf358d5f2 SHA-256: 233f67e67502b839389f319b1e6176322913d5bb527e7e775f35d6294c3279fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains a link farm hosted on compromised WordPress upload directories, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the presence of numerous links to potentially malicious sites points to a tactic of directing users to external resources for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161316b1c5aee6---36091660442.pdf In PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/30479332030.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/fejitujo.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/8114036442.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/zufosokunugobomidorototul.pdfIn PDF document text
    • https://maggievanostrand.com/uploads/media/file/64404493075.pdfIn PDF document text
    • http://bezpiecznamlodosc.org/files/file/volanuradukosawosi.pdfIn PDF document text
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/93493883068.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/24152682998.pdfIn PDF document text
    • http://ore-processing.ru/d/files/68002590538.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147afe877a2d---6677391896.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/af38391659cfa11c07d1526868bd792a/56600902761.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/ligenekufunufosejajuz.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/medexevanu.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353f502aafa---99158550232.pdfIn PDF document text
    • http://blfimmobiliare.com/userfiles/files/27835597518.pdfIn PDF document text
    • http://kyea.org/imageuploads/vimirofenitisoritobom.pdfIn PDF document text
    • http://precisao.org/files/files/9838650872.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/fupufubegebibezazinizok.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/oq5hml6ugvk2p4mkboqkdgpdqn/18387200748.pdfIn PDF document text
    • http://tahi.hu/ckfinder/userfiles/files/difar.pdfIn PDF document text
    • http://bushurov.ru/images/files/92906126674.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/marepe.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/16525592274.pdfIn PDF document text
    • http://ambulatorioveterinariorigolon.eu/userfiles/files/57767902017.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=android+udp+clientPDF 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_off0000b542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB542 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD54 16172 bytes
SHA-256: e1766387ef8077af19a2d323e81c06ac7a85498c4a998b0670223f36b453f98e
font_02_sfnt_off0000f6cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CF 10260 bytes
SHA-256: b666469ef97590e78991dd98a12623ec82995ba7d9f7d118cfb62e559b45d0bb