Malicious PDF — malware analysis report

Static analysis result for SHA-256 281d86ce44c12995…

MALICIOUS

PDF

77.2 KB Created: 2021-09-06 01:29:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 1c739e90f0af8fefe934872dc5f439ea SHA-1: 7a5f741f9495289962a88314b1cd6a760f6e05ad SHA-256: 281d86ce44c129951e5503d2572056de8f8202bc76b1f4c0a52c7f77eb173135
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 0.9973

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://pelicanfinancialnetwork.net/ckfinder/userfiles/files/nujemuvefilukifas.pdf In PDF document text
    • https://anukulagrotech.com/userfiles/file/liralo.pdfIn PDF document text
    • https://drlanda.hu/user/file/11331537855.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/1825866245.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/xowowijufuvewo.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/pj15r5j2cjl2d16ph5ltp5onmk/22059892202.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef5937a96f---52961660069.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/41722920071.pdfIn PDF document text
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/76380342931.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/lufabivujakiboganowipek.pdfIn PDF document text
    • https://isosklo.cz./uploads/22314535560.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/vegukogepek.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16072b8a4e1fdb---fogukizepawaxitupufef.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/82545963559.pdfIn PDF document text
    • http://deficanderel.com/clients/6/67/674a09facce11b7629d390eef9534ff9/File/tupugutiwarevotumatin.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/27230393455.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/fe23dfebaa809ca1385251919cffd815/rulitiwav.pdfIn PDF document text
    • http://cohensevents.com/clients/74638/File/xegepoxajaparogogijexew.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbfed6425e---99254153384.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/wurofomowodugixatiji.pdfIn PDF document text
    • http://esipro.lu/userfiles/file/56585863619.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/pifoburinofuxonozumosum.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/5fcs0ed5q5g18bjuhbr30f85qq/gipiledasuzatuxujiber.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/zezezetelujo.pdfIn PDF document text
    • https://asi-filter.pl/files/file/dofiditipelisumibige.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=introduction+to+plant+physiology+william+hopkins+pdfPDF 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_off0000c5db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5DB 11280 bytes
SHA-256: c8ae093c0904e2ab11c878fd07947bdbe3a745a99a42cfb57a8570e0c47919b0
font_01_sfnt_off0000e002.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE002 17756 bytes
SHA-256: dad23d56a066af6dae19db184db2bab7d0c007a23bc81ec0bc2e7e3a232fe879
font_02_sfnt_off00010e29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1