Malicious PDF — malware analysis report

Static analysis result for SHA-256 70d541a21a08390e…

MALICIOUS

PDF

86.4 KB Created: 2021-09-01 14:30:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 84c83bdca40380d2eda07a91146dacf9 SHA-1: 5b0b2de7ff4e2d3fda15922d241bb3b322bc4d53 SHA-256: 70d541a21a08390e772ad0ed200b05356e10ef8b00c6bc94b5de2953f8b9ada2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. It also features a link farm pointing to multiple domains, including compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the final destination and evade detection. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=different+breeds+of+koi+fish PDF link annotation
    • http://tomnhenryanderson.com/clients/8/8a/8a1068334c160bb49438aafe8043afff/File/ledokixot.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/pafikefabule.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/4558390914.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f533fdcc5e---vejagoke.pdfIn PDF document text
    • https://tw-itemaos.com/ckfinder/userfiles/files/39335681040.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/buvotuje.pdfIn PDF document text
    • http://ebonit.light.bg/includes/libs/ckfinder/userfiles/files/55113079853.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/s2k19fkurjps6vmbbav8vu7i54/54752954811.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/8be2ff23995852a5c64facc3d0c0a514/32843179365.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a6909bdd359---70638351188.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ec9cd65a038---38930130977.pdfIn PDF document text
    • http://allycatering.com/userfiles/32963103402.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/kaligoluwelajewob.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/bff2ed56a76bbaef578ddf3c9d9858a9/dexuxafadavodiribuj.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160740e109434a---pepita.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/valosamatafunagedajakor.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161078b605c900---86815330522.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/pexitolirobaluwadusokaf.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/suxikuwoselosanelipivura.pdfIn PDF document text
    • http://profil-metall.de/content/uploads/file/bipekuzipijapujagubami.pdfIn PDF document text
    • https://i-chat.tw/js/ckfinder/userfiles/files/50258896732.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841adf9ae66---migalowoketawarovinurumek.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/63037594113.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc2f5aa824---51534193793.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/2103733111.pdfIn PDF document text
    • https://milsagliksen.org/upload/ckfinder/files/59338400482.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160cf77d6bd4ed---1819509217.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_off0000ef60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF60 17128 bytes
SHA-256: 6e793758972c713f1c1089166cf8698d696db4bf30589c28493f99a322293a00
font_01_sfnt_off00011b84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B84 10476 bytes
SHA-256: 0c6cb01847a4d0bbeb0cd315ae214bac2026b4925f6ab691343aaeddee7e3827
font_02_sfnt_off0001333d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1333D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1