Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf7d227c9e487f5e…

MALICIOUS

PDF

79.4 KB Created: 2021-09-21 00:35:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fd992e9a472b1325d636902ebcf6384e SHA-1: 1f018725ab35076cc2a3c49a607d4f1d9291a2f3 SHA-256: bf7d227c9e487f5e1d31db3858b2404941e919f2e91ef6c984294202f99c10c2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristic analysis revealed it functions as a link farm, with numerous URLs pointing to external sites, including those hosted on compromised WordPress installations. The presence of these links suggests the document is designed to lure users to potentially malicious or phishing websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://nomylo.ru/uplcv?utm_term=top+10+live+tv+apk+download PDF link annotation
    • http://sinners-party.de/media/file/33152086797.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210921050125.pdfIn PDF document text
    • http://theponghop.com/upload/files/tajemuvusipigujoxel.pdfIn PDF document text
    • http://ibshop.gr/uploads/_uploads/files/6293103609.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/najitaf.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138468894df5---filijefutubedogekud.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/vuzip.pdfIn PDF document text
    • https://safe-international.com/userfiles/file/34271677531.pdfIn PDF document text
    • https://pelicanfinancialnetwork.com/ckfinder/userfiles/files/wowevebexudag.pdfIn PDF document text
    • https://kfmaccounting.com/webroot/img/content/files/tuzokadamuz.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16148fa5fe4b35---megope.pdfIn PDF document text
    • https://hocaukhudothithanhphogiaoluu.com/asset/site/files/lazudelimelido.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/161321cbf30a4f---xikiw.pdfIn PDF document text
    • http://morard-mcf.fr/data/Files/jopixupojejetalafib.pdfIn PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/tukavixanunanu.pdfIn PDF document text
    • https://ciela13.leaddeehub.com/userfiles/files/dufaleze.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/diburidasoparexese.pdfIn PDF document text
    • https://ppntassone.it/dati/upload/file/745083683.pdfIn PDF document text
    • http://acunambalaj.com/adenoto/upload/files/bexukemiwelesotazoru.pdfIn PDF document text
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/lojenovinukorixurefodibu.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/vudovulego.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/lifivadaxegaxabiwepo.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_off0000d256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD256 17864 bytes
SHA-256: 5a67a25a9dea8c5e07cce56b68b504916c5331ab06fac2bae6546bf55338984b
font_01_sfnt_off0001005e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1005E 10496 bytes
SHA-256: d58066916c4da883e44f4106f993ed73c91db2067e66aa8f5286ae7c27e4865c
font_02_sfnt_off00011868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11868 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1