Malicious PDF — malware analysis report

Static analysis result for SHA-256 3811a518813986b9…

MALICIOUS

PDF

87.6 KB Created: 2021-08-24 13:33:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bf820523b661b72880122f9ae47c38ee SHA-1: 1b30250227921934c175f57dfb116446f625f0e5 SHA-256: 3811a518813986b9189b78d47f7049f98bd71c698ec1a2ee0618885dbb5b54f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to phishing or malware distribution sites. The presence of external URI links further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://ketchas.ru/uplcv?utm_term=racked+with+pain PDF link annotation
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610d8d65c1caa---kamefagezikimi.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/httvjjhqvl14dlaerkcsaseel5/midunofe.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/69d6260ac01d319f5b9bc18debc99f6e/98698682444.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/21756334902.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/bazanuzosabafatu.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/777cea990bdde6eaeb4f481acce80e4c/zujidorisudizexupimo.pdfIn PDF document text
    • https://adlinefor.com/home/webagen/public_html/korn/data/file/gavumisokiv.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/panitofum.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/61128684703.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29f98791bf---livudafofofawumimivut.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/midalukatodogala.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/saniwanad.pdfIn PDF document text
    • http://gilbertthomasreunion.com/clients/5/5f/5f56fe696be94dde62972871c8a9bc28/File/vatolag.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160a0df9793289---wagokilasaveju.pdfIn PDF document text
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/6jbmk93b9mhilhroonhde4m9d3/15998214981.pdfIn PDF document text
    • http://benrassam.com/uploads/files/fojapazaputegemoriz.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/bofabo.pdfIn PDF document text
    • http://computerdoki.hu/user/file/94733262621.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021051606544452.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/vinuwazod.pdfIn PDF document text
    • http://coiffurenais.com/userfiles/file/10892767349.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/debedanakufezikitoveroz.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/deposovidawolugadodo.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/d724686db75624fac7d075e359eb0e41/kafepagumabuduvofu.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB4E 18204 bytes
SHA-256: a00a0c294c77b37aab9827e91e2f7034072264a8db8cf21e2a38c406d271c066
font_01_sfnt_off0000f7d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE3 16084 bytes
SHA-256: 35109fdd8dd35b109c786b52a8f168f8bd7c5a3e5cc579fc14886f540662eb1b
font_03_sfnt_off0001393e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1393E 10400 bytes
SHA-256: 0946720a087fee2b9034529aaa1877b131a8ff4b7b4a6747f6ce9251ac43b93c