Malicious PDF — malware analysis report

Static analysis result for SHA-256 88b27e9f340967d9…

MALICIOUS

PDF

88.4 KB Created: 2021-09-10 07:13:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 688ed68cffe83b23b3bc825bd50139e2 SHA-1: 9d915b6bef0d8ea08df054607b04b10b982cacf7 SHA-256: 88b27e9f340967d9bea7eee3eec71d4c99c7de7edb1e2f8d16de45371323b04a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the PDF structure itself are indicative of a phishing or malware distribution lure, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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=keeper+of+the+lost+cities+everblaze+read+online+free PDF link annotation
    • http://occahomesearch.com/userfiles/files/52265930117.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/83806872086.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210905024957.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/ghnsrfmaib3cd60nr1h9vpj6oo/50752724727.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/xunonoruwunavutuxawobuwa.pdfIn PDF document text
    • http://miydz.com/mingyi/images/userfiles/file/kobobotun.pdfIn PDF document text
    • http://uhorder.com/upload/files/30138127804.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/febokerujegigexej.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/47714415628.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132750584bd3---84750087491.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/56762607175.pdfIn PDF document text
    • http://awards.nl/img/cms/file/jotetodejoposobelara.pdfIn PDF document text
    • http://biirbeh.mn/images/content/file/35032670000.pdfIn PDF document text
    • http://cpviettin.com/upload/files/xapowezimikujidixitokok.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/50721495057.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/30515946253.pdfIn PDF document text
    • https://tommytest.dish1314.com/data/html_editor/files/wogetaxeboli.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/13923683086.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/2672295252.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/41dd693aac12b31ca2018434cfbda131/29289020949.pdfIn PDF document text
    • http://rujiahk.com/uploadfiles/file/97021985490.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/21088549261.pdfIn PDF document text
    • http://healhumanity.foundation/userfiles/file/menefusulozamolomabesoja.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_off0000f274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF274 18252 bytes
SHA-256: b2cfa68104f09cab6a8a86f41fcee94ddbb8187d15575fbab19121fc35cfa858
font_01_sfnt_off000120fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13913 10976 bytes
SHA-256: 968b8947211d0b5a777c01eb94b0d685a1c46a93eca0e7f4f58418d8b8e7cb2a