Malicious PDF — malware analysis report

Static analysis result for SHA-256 c75a325950a84a63…

MALICIOUS

PDF

79.8 KB Created: 2021-09-15 08:58:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 73b767cca7f5c4774ea1358759e21823 SHA-1: 337974c8086973806fdc96d0540f9e49ef3f16f1 SHA-256: c75a325950a84a63ec54262f84618eb4a5c9d27a8f6cd721ac66e70bd01a9bec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to other PDF files hosted on various domains, many of which appear to be compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure suggests a link farm designed to obscure the ultimate destination of the user's click.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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=ad+free+sudoku+android PDF link annotation
    • https://satbietthu.com/luutru/files/64717929916.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/88668839915.pdfIn PDF document text
    • https://vinamex.info/uploads/news_file/15204547715.pdfIn PDF document text
    • https://mumegram.com/userfiles/file/81458305258.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/10671579776.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303121aff2b---zunemikikikubabiju.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/vekogarelobipo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff1ead9966---vufax.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/87844335894.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/fudolujutugepolililibiko.pdfIn PDF document text
    • http://vibestedu.com/_UploadFile/Images/file/dipujozivegovoditivux.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/tv013gc8s96rvf8oamkabnm7gd/venegetamafisupo.pdfIn PDF document text
    • http://gpe-el.pro/ckfinder/userfiles/files/rizodexatixan.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210908155412.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec9e15825b---fowumetomamitogib.pdfIn PDF document text
    • https://sarenpinler.com/calisma2/files/uploads/selelazapegitebelatojed.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/venirapexisugewapeg.pdfIn PDF document text
    • http://0575zl.com/userfiles/file/82400418045.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/xufexowazopeledo.pdfIn PDF document text
    • http://nhatrangpalace.vn/app/webroot/upload/files/27624347892.pdfIn PDF document text
    • https://lotte-ppta.com/beta/assets/file/16241334247.pdfIn PDF document text
    • https://printsolutions.ro/uploads/wysiwyg/files/lubajopigefezow.pdfIn PDF document text
    • http://bestpokeya.com/uploads/files/vafuputusapelugaxi.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/47e91d86edd1f4b5315e57c9f48f9fcc/bubide.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_off0000d4cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CD 10376 bytes
SHA-256: 19f551014b3c5fed2cf6c0d3b03f13ee39d0d428e75b5776d15f7fefd16b9500
font_01_sfnt_off0000ec5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5F 17680 bytes
SHA-256: 6df9ad6f9648770d92d8fb79b5420eb9ebd3b17436d26a9aeebe9eab55351df9
font_02_sfnt_off000119e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1