Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7a66a667e89bc50…

MALICIOUS

PDF

88.3 KB Created: 2021-06-28 11:22:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f8b08c1c31c5784747c806ed97d146fc SHA-1: 1487edd3beda78ab587c239855610aa7d13dd1d5 SHA-256: e7a66a667e89bc50edf831034def3f534654c16043d102857f0783f3c9272b01
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for exploiting PDF vulnerabilities or redirecting users. It also features a significant number of external URLs, many hosted on compromised WordPress sites, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://krisoc.ru/uplcv?utm_term=ages+of+kohlberg%27s+stages+of+moral+development PDF link annotation
    • http://ekotronic.eu/files/file/38347868534.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/a81846c325020799e0d50ce7a3084871/ferijaxibijoxuxerogubibat.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/7c4e288103966e906d180859ef7397ec/gebizotanaruvuzo.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/78096683497.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/44772923437.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160be69d78f95c---ranuvujujabokok.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16092df3bc619a---41286099171.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/bba211d0bcc585a8b9872a1504cdae52/26933714947.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c9daddb3d3---ziseja.pdfIn PDF document text
    • http://grandchainfamilyfoundation.org/clients/85333/File/pelosonu.pdfIn PDF document text
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/93ff9f683a9cd79c65f68738eaff629b/lavezariso.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed36078f43---11074979604.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e0b6260aa---zakosepolu.pdfIn PDF document text
    • http://awkontrakt.pl/ckfinder/userfiles/files/49955922383.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16098396aa0ca9---37795274001.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/58461035794.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f80f2a7ce---pajeponiwulofatu.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/bc70fa9767e973da7da025cb77ced48c/mediguwimetobevorelusotuw.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/hp46rk2ffdktjbqvqffb0arqe7/ruwoze.pdfIn PDF document text
    • http://anhopphat.com/uploads/files/7918560471.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d317c6c8d7---sovusiv.pdfIn PDF document text
    • http://ucity68.com/clients/e/ea/ea220da86df44fb0ae3b7c8e8295ccc1/File/junimawimovikulalinenix.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087cccb7caa0---vosevomokarefo.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/25332886028.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_off0000f40a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40A 11164 bytes
SHA-256: 2cf2359fe42754b18034ec4ea5bb7e8ed1e23c6bf52cab445451e3021484292b
font_01_sfnt_off00010da5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125B7 17664 bytes
SHA-256: 932de82bc1d31ef6901ce9a4dbd5a1de9fe4c40c3e93f55993934ebb2979d61e