Malicious PDF — malware analysis report

Static analysis result for SHA-256 68e72421155277cc…

MALICIOUS

PDF

86.4 KB Created: 2021-07-07 06:10:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 84f43255b48bd9f4d1e8e18449cd5738 SHA-1: 538ba78341a5729b62852dff64950fa241e31dbc SHA-256: 68e72421155277cc743a22ad6a2717cd463259f298cde81e0d5845761a2ad8c6
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, as indicated by the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to download further malicious content or engage in phishing. The embedded URLs are the primary indicators of compromise, facilitating the distribution of malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://envomask.com/wp-content/plugins/super-forms/uploads/php/files/810e9479db36faa677f792a58003778a/feveguvof.pdf In PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/2891af9dcdac98aeced477723842fd87/pedasegexilimo.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/buxifaw.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d7e8ab08d---85920756939.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d3ff2662c08---93934346596.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/o7r4i36ccvsjke7r19rmd507ee/37950320494.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/eeb31098dd7170e5b5df81e192d62c98/gepabiwularilufumoduxet.pdfIn PDF document text
    • http://hk-dcc.com/wp-content/plugins/super-forms/uploads/php/files/13r2rum0cofgufebn6ju8np8qe/98861948746.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16091c09d5dd0c---ximukijebakezidimonuxa.pdfIn PDF document text
    • http://johncarroll1967.com/clients/1/18/1896e795ecc2602204d707ec4e69586f/File/4720033592.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d39e898f91c---29981291471.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30476db268---1998177066.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160be373bb852d---52580904998.pdfIn PDF document text
    • http://yuhongzg.com/d/files/97695478440.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/55udkq583d2g8b29e4l8ttdrnl/30824271587.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/db29d3ba69a3cc6f5071d5cfd44ac51f/94734517690.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/695f3553ad728e11bd79f4612691eca9/wibivesipuvebumubusi.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/qdkn9pueu2v05cqi1nsqa4ilr0/2452538307.pdfIn PDF document text
    • https://peterdegendt.be/file/35243186051.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1608c05b46dd95---pomoxemu.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/d32ed726998b0309a6b654b6c25ce6c3/wefosuvojefixowadaraxi.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/39b25296b76a6a3406ca446313999edb/65718214514.pdfIn PDF document text
    • https://master-service.ro/images/file/dowaludisipiz.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb9ef02e96---tomigozokezuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=two+letter+boy+namesPDF 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_off0000f00d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00D 17136 bytes
SHA-256: 7731972e607e1b2d1a61c52f2f9b5d31f62219c4330e06de6db45c071701f87d
font_01_sfnt_off00011cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC8 10480 bytes
SHA-256: 73659fbee8b508e5d37228d05278cd27e561ed238ed4ef2daa2f0a36a66a94b7
font_02_sfnt_off000134ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1