Malicious PDF — malware analysis report

Static analysis result for SHA-256 21fd2a5482f4ecfc…

MALICIOUS

PDF

110.6 KB Created: 2021-06-10 22:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 500564975478f559122eb5647a61995c SHA-1: d9316f4cc8544f6c80acedf5ec66b14b679532c2 SHA-256: 21fd2a5482f4ecfc1e3a0f5897dbf6e8cbce8d2a991bc730a9a7d52e79ea53af
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nomylo.ru/uplcv?utm_term=tabla+sistema+metrico+decimal+pdf PDF link annotation
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/qf8l64bkcregeiegl9ds9ajh66/32046341581.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160910b4885326---72736737837.pdfIn PDF document text
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/cc456ad56dd3797bba9916666ecd5296/ladoxuwotinalij.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/fmgsnppbm57os1e208netg1nqf/wunukarepewidefemazexilu.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/97297251179.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ac5378afd---76478763833.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/8dffe18ee8f6c080651f7c5fc351d680/12843885093.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160b515b2b684e---xajazudilidijol.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/f7a41bb21c58ec00cc332074db99dc03/xofexiwevajo.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/44bbd1e8d7796f442fdf85e566a1f96d/48411411810.pdfIn PDF document text
    • http://mazurubezpieczenia.pl/zdjecia/fck/file/29644803998.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/zupakezelemureguva.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/e7be0b817e193cfadfcf6cd9357f04b1/xadazoxedosi.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/ganopagaruvifuvogiw.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/53815786232.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ede2c63fa3---tazalopigagewobeb.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/hc1dtm7c3plkor68156rlikal0/bajusex.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015c75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15C75 5072 bytes
SHA-256: 381a97e5d44b2cb79a10dc47e45fa6f3c2b1fedb5a13416b2a2e3743d1c0fb2e
font_01_sfnt_off00016da5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DA5 15000 bytes
SHA-256: 4a04e1ccd7311027d13e7af6224083b7c2e75af8e6b92d477e84f52b5b49e494
font_02_sfnt_off00019da4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19DA4 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2