Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4df7439f83c2ff1…

MALICIOUS

PDF

94.4 KB Created: 2021-07-15 13:11:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 02cd5b83b8a868806db7dedfdab5a870 SHA-1: 5de29e4ca17ffbda3c178535daa605f656a272a5 SHA-256: a4df7439f83c2ff1af630a2a0372589dac8d94c09e6e78d9010e1f1b2ac9e882
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous embedded URLs, many of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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 http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609caf035355b---6691717849.pdf In PDF document text
    • https://appvid.eus/userfiles/files/jekosejuxofetezaruravawu.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/ruvuzufe.pdfIn PDF document text
    • https://samudra99.com/contents//files/70631211661.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f7ac98cb3---12921601896.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb614d3a37---nasawuwefirov.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/a486497b9e5936cfe2a00400e6e526ed/66151671747.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c90125137fc---gitiduxum.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/nebexojogudulizisugowuxiw.pdfIn PDF document text
    • https://inverpalmas.site/aym_image/files/68660917758.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/31719270692.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/9dfc11aa5bb3b908dc51ae61a211acf9/87721871705.pdfIn PDF document text
    • http://snsi.jp/image/news_file/76054688867.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e00e0dcf433---25955919387.pdfIn PDF document text
    • http://ketoanantamhcm.com/uploads/files/ranetujepomaresi.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8be2a5059---92270691377.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/45744030066.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c97b5ee07e8---98229890300.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160793ab98fa1b---meboz.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/pulopidizonuxef.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c133e5a71---suzofexokeronuguk.pdfIn PDF document text
    • https://argumentua.com/i/file/pafipigibuzugolokesime.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9d8956352---xupotivobujolinemafawojab.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/eace69d40875e5add73d1ddd9a8a3d45/79660064143.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/iv6efpnrrum6lddprgmoh2iul5/wujidugudoma.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/musewotewinanasas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=sift+army+aviationPDF 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_off000110b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000128ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128CA 10284 bytes
SHA-256: d6875c793bb86fc8645354502bcf877c2654de1c03aae127d763154ac2a2b11c
font_02_sfnt_off00013ff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FF1 17104 bytes
SHA-256: 80dff39f6cdfd9d421ac35462b5a4864d308433694cd8c40e36fea5a9c112ede