Malicious PDF — malware analysis report

Static analysis result for SHA-256 88511a239adfcc9a…

MALICIOUS

PDF

106.1 KB Created: 2021-08-10 23:36:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: e6c22525d5ada1e0bb080189dcb00b7e SHA-1: d2da408978273cc616dc32968f9297fd035849ee SHA-256: 88511a239adfcc9abfeff38b01cb208ca91ae52108375966ed0aa5f4f29cf25e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads, suggesting a phishing or malware distribution scheme. The embedded URLs, many hosted on potentially disposable domains, reinforce this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/072bc31932f596a7d0ddf6b533f934bd/figuga.pdf In PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd069366914---jojuvefobomupefasimowumu.pdfIn PDF document text
    • http://montpellier-business-plan.eu/mbp/upload/images/images/upload/ckfinder/lanavutawimokolo.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd3048a632---33676519548.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/7a42944b9f572315b1f621c8ae6fab5f/39158346716.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad936a89265---54528325418.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/5a39e98d134e2b456d88f834660c55e7/xojetipegal.pdfIn PDF document text
    • https://la-klamm.org/userfiles/file/62552560088.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/92616174952.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/41531752758.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/87568542047.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c19825496---64045431920.pdfIn PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/32777739393.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/47163128440.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/sagasidojosulonedutatedi.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/i5i3g882huin7igpht4eh43vf3/98059667001.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/73659601184.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609265f2825de---78734149369.pdfIn PDF document text
    • https://asiarsolutions.com/userfiles/file/56781132673.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/pubifedunadimid.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a3de80ebd---tobilutumijuzetoloka.pdfIn PDF document text
    • http://ngnjl.com/userfiles/files/43384381381.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/50682483031.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=fill+in+the+orbital+energy+diagram+for+scandiumPDF 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_off00013856.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13856 11252 bytes
SHA-256: 5ea25824edd27a659feffc744bd9976f9160bab89b5232069c2fee5096ff2532
font_01_sfnt_off00015251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15251 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016a63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A63 17568 bytes
SHA-256: c823d8ad0ca99fd9038d6f9f3749aaf790c80a6e0316dc5e9b83bfcb9d0be882