Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb40d61cf5d20e54…

MALICIOUS

PDF

68.9 KB Created: 2021-09-10 15:28:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c8e5c09e7f2770478bb1a75fe6694cfb SHA-1: c2442e9f4a18abd337e5a53cc82b0c930a507268 SHA-256: cb40d61cf5d20e54c34f9e7a5a394cb42f5af084127fc351fe8b3a0ad21f7127
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is flagged as a phishing lure by multiple heuristics, including ClamAV. The document's structure and heuristics suggest it is designed to trick users into clicking external links, such as the one pointing to 'synerhu.ru', likely to download malware or lead them to a phishing site. The presence of embedded JavaScript indicates an attempt to execute malicious code within the user's browser.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 2 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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=free+download+crazy+taxi+for+android PDF link annotation
    • https://isigakizima.net/img/tmp/file/31318707078.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021090510143173499.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/38040495736.pdfIn PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/tezerawaz.pdfIn PDF document text
    • http://jl-vacuum.com/upload/files/valoruverute.pdfIn PDF document text
    • http://kingsauto-bar.com/js/upload/files/25573829403.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/lakebejipan.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///lixirekukesapimesaropi.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/retelebeve.pdfIn PDF document text
    • https://www.ftha.org/admin/ckfinder/userfiles/files/1923553646.pdfIn PDF document text
    • https://lazdynumokykla.lt/userfiles/file/69857688454.pdfIn PDF document text
    • http://nanopena.cz/upload/file/pulerufowewovat.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/38048828902.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/jemipusupinamotamujesi.pdfIn PDF document text
    • https://areicon.com/images/file/zevelido.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/23300054448.pdfIn PDF document text
    • http://k1a.ru/images/files/file/65758812225.pdfIn PDF document text
    • http://osayit.com/images/file/goras.pdfIn PDF document text
    • https://ptogel2.com/contents/files/82334912325.pdfIn PDF document text
    • http://ateliergermain.org/sites/default/files/file/82942729397.pdfIn PDF document text
    • https://daqing-jewelry.com/uploads/files/202109031659135696.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/uh22h8f0bia16m9rreqrt56rp5/85928341286.pdfIn PDF document text
    • https://matratva.in/userfiles/file/81096933426.pdfIn PDF document text
    • https://actor-conseil.com/files/file/zutawodubot.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_off0000af63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF63 10640 bytes
SHA-256: ceda1157c38c90be1d2838f08bdfeda12aae6b74a204588cb1e8d2f7db9f2b96
font_01_sfnt_off0000c7fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e00c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00C 14384 bytes
SHA-256: e6aadbd556995cc00ec3d2460c0ee1a58962e4db0f6b8a24c80999d7a8a87912