Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaa792394a1f3d33…

MALICIOUS

PDF

80.1 KB Created: 2021-09-20 14:17:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7cc9eb84c7a74fa475014e50eace7ed2 SHA-1: 08a8245981059c9e7117f02a38594e2c4f5b5d2d SHA-256: aaa792394a1f3d3369021494b45762cc0a26a0a25ca1cb16f60118726a9d4269
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm designed to redirect users to potentially malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of hosting many links on disposable domains, suggesting an attempt to obscure the final malicious destination. No scripts were extracted, but the overall structure and URL distribution point towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://wastran.ru/uplcv?utm_term=idm+download+for+windows+7 PDF link annotation
    • http://lotusburbank.com/uploads/files/kusojasago.pdfIn PDF document text
    • https://lwim-ouargla.dz/ar/files/98463042943.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/82554954996.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/falijuxotuni.pdfIn PDF document text
    • http://ttmm.co.jp/ckfinder/userfiles/files/rutomivaf.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/25006726994.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1631484119.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613be5e3f2905---wevoropo.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/bonozipemidubazaduto.pdfIn PDF document text
    • http://bibonatura.com/ckfinder/userfiles/files/zugolo.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/somebonuzasawej.pdfIn PDF document text
    • https://kit-veron.my/ckfinder/userfiles/files/vidafevuzuxasizokopebu.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/tobosetujuwebunutudo.pdfIn PDF document text
    • http://www.romanschatztruhe.de/img/files/zevotezuke.pdfIn PDF document text
    • http://kccmaul.com/files/files/46937153861.pdfIn PDF document text
    • https://wasael.com/userfiles/file/vepukotam.pdfIn PDF document text
    • https://oteaexpert.fr/cite_imgs/file/rusezorumajabadoza.pdfIn PDF document text
    • http://saxonrt.hu/img/userfiles/files/76063746386.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/letejiwanomanevajuro.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/29115895452.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/76352677002.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/xaberu.pdfIn PDF document text
    • http://ceroki.com/image/files/63491468004.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/98568401797.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_off0000d8a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A8 16484 bytes
SHA-256: 2f24fec18d9fbf3e8588853e37c9f400c32a7327b1fe662c5294201e0ecac8a7
font_01_sfnt_off000102f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B0F 10372 bytes
SHA-256: ca1dd9a89113e2ca1d8e3fbb16fbe49b5dfb25c2287564113b1bd970896b55fc