Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a19b34d5ffc03c6…

MALICIOUS

PDF

100.7 KB Created: 2021-09-19 00:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b9d78c4acbe28a64515aabc5b32f14dd SHA-1: 62683bca9f543c402af76a77686b152c62344c51 SHA-256: 6a19b34d5ffc03c6bc2cedbb26f991cacd96a13db8bb330bc23b91fe7044543b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=upgrade+windows+surface+rt+to+10 PDF link annotation
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131a1dbaaed2---putubidanujamudid.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/nirugeporadaduxoguvut.pdfIn PDF document text
    • https://maxflowfans.com/userfiles/file/deregulobirofix.pdfIn PDF document text
    • http://trongtinpc.com/luutru/files/zejixifav.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/mirijitulowabim.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/80937413892.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210911_89C4BC287843BEEB.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/wujugozutibavowuvimajido.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161328733baea4---73461080451.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/semanikuxu.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/gofukazo.pdfIn PDF document text
    • https://eltdb.com/UserFiles/files/lonigaworetuserekumal.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/gd6jab1vaq5m0ule7mi2lshk53/gafizotamimiwi.pdfIn PDF document text
    • http://yh-nutri.com/filespath/files/20210918215756.pdfIn PDF document text
    • https://lensmam.com/userfiles/file/94591801981.pdfIn PDF document text
    • http://ceomit.com/fckupload/file/55820023639.pdfIn PDF document text
    • http://namkhoabacninh.com/images/files/rotizezisunusazedor.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/13716126538.pdfIn PDF document text
    • https://remini.hu/userfiles/file/zuxosubuzuzan.pdfIn PDF document text
    • https://dreptultau.hotnews.md/upload/userfiles/files/zukede.pdfIn PDF document text
    • http://klenderbio.com/upload/files/wajerutula.pdfIn PDF document text
    • http://zeshengtecphar.com/UploadFiles/FCKeditor/20210914112549.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/jisakagov.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_off00011efc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFC 11116 bytes
SHA-256: a8a20d0b8fd78ebca3c1b87a5aaae619b519ce90f68a3265aa5e3b48e8802df7
font_01_sfnt_off000138f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001510b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1510B 19588 bytes
SHA-256: 36ccebde64a022e64b1357807b40d4f3429f4c942e06a48e81f912880095250e