Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c61f4d5548eba98…

MALICIOUS

PDF

83.0 KB Created: 2021-08-22 04:43:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 445ebd348e3ef44e109f941a2a30ae73 SHA-1: 10866608edb287f747f842e70e7810f2115b759f SHA-256: 6c61f4d5548eba98c57ec5961ee202e4a6500d6452c01670d57e46e08d9b7a15
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://agendatourvietnam.com/hinhanh/file/14101059722.pdf In PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8faacf2f1---bexapener.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/knf8o7qtnvi62aidcn0o83arjl/16323420215.pdfIn PDF document text
    • http://indecomavo.pl/inc/78965931310.pdfIn PDF document text
    • http://geose.ru/userfiles/file/43213309550.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/95966776335.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2987f5dedc---gikeju.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/75698916038.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/1vcnfkf6mh2a48r5s2rm9q5fk4/gidufodetubusavuza.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/s0crol5njqbrhhe9qi62gbjep1/pemoxazoxilajasewepef.pdfIn PDF document text
    • http://www.sec-ollivier-associes.fr/www/upload/file/29214432304.pdfIn PDF document text
    • http://abwlanham.com/uploads/files/vivegofid.pdfIn PDF document text
    • http://aahsclassof1978.com/clients/b/b6/b6117739535924054831d33ecd54b00a/File/lebeselafexobi.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160800bdfb2904---xemororexepudoledak.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ae00439c953---53427727023.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/4374f66a0f62507564a222f5cd0d9e06/bekigofovuwikunefa.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/d4e9ceade1f7ad61681ef0303fa011d2/pakapenelisejegavi.pdfIn PDF document text
    • http://e-store-sys.com/userfiles/file/13418314409.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/lopidedaz.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161001bb048953---7015175937.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac42c31b24---64986446393.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=phonics+workbook+for+kindergartenPDF 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_off0000df7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF7D 16928 bytes
SHA-256: 1ce38767024145d241e645897de1e02401ccb1126a941f26b313705688b697eb
font_01_sfnt_off00010bd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD7 11028 bytes
SHA-256: 5c763005212a42f3a445e14adc8f2e8d07d5eb8a9a7551dd3ada167a1ab64c16
font_02_sfnt_off00012558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12558 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1