Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7ec2dd1acafd090…

MALICIOUS

PDF

83.2 KB Created: 2021-09-03 16:21:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2ae8f774ff11ffcd6a7b498343e6fbf6 SHA-1: cb82eae182bd26f9c16ca863ac2513274752e79b SHA-256: e7ec2dd1acafd0901a2064e38cc9b26cbfb8d56b53299d02dc1321a1b5b035b2
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, with several heuristics indicating it functions as a link farm. Notably, some links point to compromised WordPress upload storage, suggesting a tactic to leverage legitimate but compromised infrastructure. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://queure.ru/uplcv?utm_term=unlikely+heroes+5e+pdf PDF link annotation
    • http://domario.ru/userfiles/file/71367881770.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021060209075873499.pdfIn PDF document text
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/gakifuvulevilewalox.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/a7da5e3d32649b024b99aa8e5766f692/munixojininoz.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/13617547636.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/36hfsldlgotr34t36idfc3ocd2/tanowevovezubavamo.pdfIn PDF document text
    • https://jin-ji.com/upload/files/witavisajokasava.pdfIn PDF document text
    • http://mousike.it/img_ins/files/zexukesapefimubejaniv.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1ab7f63655---28536346247.pdfIn PDF document text
    • http://tutaylamhet.com/storage/ckfinder/files/26970972709.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/12303496665.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f1368c5a4f---92802347720.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/e691c20100c1abd941693c7a59567f4f/55916652849.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/509c70af451552ed4baefd56bfc4a352/vobirakuviwefuror.pdfIn PDF document text
    • http://tebsc.com/clients/84181/File/weroziwoxanigutawi.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/64990668308.pdfIn PDF document text
    • https://xigmatek.com/upload/files/nikomegeborore.pdfIn PDF document text
    • http://penzionklara.cz/userfiles/file/zamimixape.pdfIn PDF document text
    • http://reklamaopole.pl/userfiles/file/zuluj.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/7667053489.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/9adec6588ba1f05dafa38981fe0e1185/97324185160.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/78275277513.pdfIn PDF document text
    • http://tyextractor.com/d/files/zisobigagamuwidogix.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/kalabuv.pdfIn PDF document text
    • http://lenosada.sk/editor_uploads/files/34695210732.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_off0000dc95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC95 10680 bytes
SHA-256: caeb6d344f05a63c6b7328a279520281f55778ba5c6ed7833fd5cf554326304b
font_01_sfnt_off0000f500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF500 19280 bytes
SHA-256: 4e0a510c5b601603930888d06fdb4720d41e84e5d097e2c042c9036d3b639ec0
font_02_sfnt_off000126d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1