Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f81b1c284ca0d23…

MALICIOUS

PDF

83.3 KB Created: 2021-09-05 09:18:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6c068f68f07ae2826e28d5a4a6b9a6a8 SHA-1: 8be7b16a9492eedafcadff96a803470a4c982871 SHA-256: 6f81b1c284ca0d239808f434d24cf074ce867aec3f2973563752c00a6892a8a2
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple potentially compromised or malicious websites. The presence of numerous unknown URLs, some hosted on disposable domains or compromised CMS uploads, supports the conclusion that this document is designed to lead users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://mlmrockstars.com/ckfinder/userfiles/files/pajasoxaraxu.pdf In PDF document text
    • https://alteanetworks.fr/img/file/xigofawetijifoxip.pdfIn PDF document text
    • http://dichvu12h.net/userfiles/file/5862475612.pdfIn PDF document text
    • http://tpt.taipei/asset/uploads/files/gamuxamaxopopuxexijir.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5d48f147b6---fugutulobubigebimolisat.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210820071128.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/37c5b7088774707ce798690fb553c3fd/89259773127.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/betodejoferotibavapapuz.pdfIn PDF document text
    • http://straps.by/ckfinder/userfiles/files/jopuvuxazupaxe.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b7aeac50055---zavifobog.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/goperuduboxikedogot.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/2d31aa285b6bb8cb8245547769488ff8/zarajafifij.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/37ebtvbijuagkhej3qh3md89p7/20575935978.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1ab11b17d---mozelepolapod.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/53714eb055a800f256071b8ffc439a78/89448275387.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/vrttinjig2vavk75ndd49nlve3/narapuwezizebopemufiga.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d264ff5843c---94475727897.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/kobeputabupazoparijo.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/4b690127e5a3d69403315d3f4ef02db8/51578607082.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/04cdcf040f943c54a63ff3d135d6eb7b/bopimu.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/divadoxegow.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c4de7f52e---gulusetowin.pdfIn PDF document text
    • http://esistore.lu/userfiles/file/63614647038.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/7e13cf2e79e58f8233c163bf35c756d8/9880575528.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/kanegigaxujizom.pdfIn PDF document text
    • https://baptistfriends.org/media/fogemimudipuxomolaruv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=olympus+190+series+reprocessing+manualPDF 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_off0000df0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f71d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF71D 17640 bytes
SHA-256: eaa4fb01aec697f89dc01f57003f02bb1a34e1cb9f0eed8f63a80079f5c8bd40
font_02_sfnt_off00012512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12512 11200 bytes
SHA-256: 6078b885eed38c5019c6f233ed86c91c0135a0548ebc9eba5507f566189448a3