Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac351cee9d883bd9…

MALICIOUS

PDF

70.4 KB Created: 2021-09-17 11:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3e47d99f57ecffde89d341f1fddd41eb SHA-1: 90b471a1b3f6f16d1f5d63b217c25a6895e17471 SHA-256: ac351cee9d883bd9ed8fce1187db6d72b387e0c252b3d3e3169a67a8da561a08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://infrive.ru/uplcv?utm_term=h96+tv+box+firmware
    • http://erbamedica.org/userfiles/files/fofidexemisazowagalozeje.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1255044cb---vozurilaxadifapukin.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/fc3a39e3144604ee01efd98d0d13f68d/834628531.pdf
    • https://accuratesearch.com/userfiles/file/dekojutiwefoza.pdf
    • http://entryexpress.online/chapter_images/files/99089496667.pdf
    • http://technology-mp.it/userfiles/files/59614131571.pdf
    • https://mytopics.it/uploads/file/sezasagiwowuparatopaxipop.pdf
    • http://np-laser.com/upload_fck/file/2021-9-16/20210916062045626552.pdf
    • https://prestinieurope.ch/userfiles/files/sutumu.pdf
    • https://nabil-doukali.com/userfiles/file/mizowatawivegug.pdf
    • http://lateonsettay-sachs.org/userfiles/file/24631746003.pdf
    • https://m-isc.com/userfiles/file/59081384890.pdf
    • http://xmzhj.com/UserFiles/file/pozegufajiworademopilijav.pdf
    • http://www.pacautomarketing.com/file/57318346138.pdf
    • https://jf-orvalho.pt/userfiles/file/38002543793.pdf
    • http://sunwisechem.com/Uploadfiles/files/tomosevufupusiv.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d62876af96---pudijase.pdf
    • https://hogozaty.com/ckfinder/userfiles/files/16871638105.pdf
    • https://vespaclubcagliari.com/userfiles/file/99767328663.pdf
    • http://zbraneklapka.cz/ckfinder/userfiles/files/67308921042.pdf
    • https://karaari.leaddeehub.com/userfiles/files/56872339517.pdf
    • http://szjwwj.com/userfiles/file///88840067820.pdf
    • http://szentimresiklos.hu/upload/file/wagunuxixofubejojotarak.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/27fbangfl891nn268nfsql70rb/vexojafagagegejigijix.pdf
    • http://clubselectionvoyages.com/images/file/76760385125.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b23a.bin
8d5988b2904f02efd4c81f515b002c23948d52f75a2653751687796aec60016c
pdf-font-stream PDF embedded font (sfnt) at offset 0xB23A 16208 bytes
font_01_sfnt_off0000dba1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA1 16792 bytes
font_02_sfnt_off0000f3b8.bin
b92b71628e046d2d31bd609e8dda2aef58d46bec39106ed5eca417f1f8ccaa47
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B8 10776 bytes