Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fb40532bd3a7503…

MALICIOUS

PDF

84.5 KB Created: 2021-09-20 14:19:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e7eff2841c7285782aef380cd69ec669 SHA-1: 56dd47db1c6416e420b221e7ff712be8dd5cbea7 SHA-256: 1fb40532bd3a75037cbd42d032a6b60235e3fd1003c599f88b1f8e80f74620f4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://ketchas.ru/uplcv?utm_term=pes+android+game PDF link annotation
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/8ba851762433249a83be6eb008ca0568/sotatov.pdfIn PDF document text
    • http://elitk.ru/_files/84459702548.pdfIn PDF document text
    • https://media-get.com/userfiles/files/17731059453.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/38071025497.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/79085713226.pdfIn PDF document text
    • http://daieimotors.com/js/upload/files/vupilizufuvidadenide.pdfIn PDF document text
    • http://dotykbylinky.sk/_subory/subory/poruwepabedisoxivimu.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161379f6742341---92000239745.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/lijofumokujatikazegen.pdfIn PDF document text
    • http://nonstopsushi.com/uploads/files/35108666572.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/xobalinurasagesokozig.pdfIn PDF document text
    • http://1-champagne.com/blog_images/blog_/file/34585883048.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/91980865306.pdfIn PDF document text
    • http://italy-ex.com/images/blog/file/lexat.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/lekegim.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f7b9a2b909---43481249918.pdfIn PDF document text
    • http://chipgene.com/image/files/20210919_060238.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/gekiwoliwokivekar.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/topoxokagixajumul.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/35648771479.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109170443534071.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161467df591f5c---2046982125.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_off0000e998.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE998 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000101af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101AF 10448 bytes
SHA-256: 275aff864c100b3155bd502c827f960acd8b6c738b71b3c1bb67e745411614a8
font_02_sfnt_off0001191a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1191A 17024 bytes
SHA-256: 15231db86c0808c2b9fb6272f297d49d55b3f84613ce13ff389d15946515a5a8