Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8742355b810582c…

MALICIOUS

PDF

75.9 KB Created: 2021-09-20 09:47:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5d72c582294376775bcfe628b86e792f SHA-1: 271d8b186e91b413d0179f0059960a80f491cd0d SHA-256: a8742355b810582ca23c71d2d0324a6e88edb2be3c2c909d32692d155c6b18bb
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for exploiting vulnerabilities or redirecting users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the numerous external URLs suggest a phishing or content-luring campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lead users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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
  • 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://www.parquesanalbertohurtado.cl/ckfinder/userfiles/files/kisanipepuxugilod.pdf In PDF document text
    • https://hongmao.tw/uploads/files/202109052122456632.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/dapozop.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/popanolexupodotu.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/jijabofurelibozinujibu.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/2327520405.pdfIn PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/42126117967.pdfIn PDF document text
    • http://boardmark.com/files/file/rapelupesijabode.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///demudug.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/79792753137.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343f446f1dc---kedibadewixixufuvukerawu.pdfIn PDF document text
    • https://takitech.hu/userfiles/file/89483371585.pdfIn PDF document text
    • https://dptech.vn/uploads/files/37760704906.pdfIn PDF document text
    • http://spakimthi.com/upload/files/19195014561.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/27486813535.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/57754159498.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/a75fc127057d6d4bee98f4d2b92ba540/kuwagit.pdfIn PDF document text
    • http://tomekorea.com/userData/board/file/44587517763.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/gaxax.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/mizugitatuvimur.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/jogekeduranos.pdfIn PDF document text
    • http://agisma.ru/files/pages/files/nuxabejukib.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/90641904244.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/84476059952.pdfIn PDF document text
    • http://wolfroccatiassociati.it/userfiles/files/82066327467.pdfIn PDF document text
    • https://naves.cz/res/file/67032836050.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=polaris+viewer+apkPDF 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_off0000c2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2F1 18156 bytes
SHA-256: 2a504315d1fdf2a817f2424e707041515e40a9162710fbe84f664daf59616362
font_01_sfnt_off0000f2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E4 10288 bytes
SHA-256: f5a59de86ee989c1b6264bc8923a62a8a6fe3ecea08c8912d41018c47eac6bfc
font_02_sfnt_off00010a3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1