Malicious PDF — malware analysis report

Static analysis result for SHA-256 5694c59da5dc1255…

MALICIOUS

PDF

70.6 KB Created: 2021-09-25 20:41:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3a33559473cc89ed98e38e63bbb57140 SHA-1: ed590adff8d65ffbd6107e76fdc07598e07c73f4 SHA-256: 5694c59da5dc1255999e7cf8c0929ec419d6de65af6165409c7fb25f6d740101
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a significant number of links pointing to various domains, many of which appear to be disposable hosting or compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating numerous small PDFs with unique links, suggesting an attempt to obscure malicious destinations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://chcial.ru/uplcv?utm_term=android+disable+animations PDF link annotation
    • http://zensushidanapoint.com/uploads/files/20761135304.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/tunifugufoxika.pdfIn PDF document text
    • https://strings97.hu/userfiles/file/wenugisi.pdfIn PDF document text
    • https://sma-dfgg.org/site/admin/file/39547210972.pdfIn PDF document text
    • http://bodegaadrover.com/userfiles/imagenes/27874897226.pdfIn PDF document text
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/fexopujunu.pdfIn PDF document text
    • http://gabortech.com/admin/file/97895096655.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161413e8381be9---fisubaxiwejogarifofuloted.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/30896065712.pdfIn PDF document text
    • https://mccartha-cobb.com/userfiles/files/48358139301.pdfIn PDF document text
    • http://metafelix.it/userfiles/files/lobanawawodog.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/dimurilusujemiwum.pdfIn PDF document text
    • http://orvositudasbazis.eu/images/upload/file/91141484413.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210909072603.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/3521546891.pdfIn PDF document text
    • https://pastelbuilders.com/userfiles/file/gijut.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/94730718698.pdfIn PDF document text
    • https://regaluxiluminacion.com/uploads/assets/file/3261871448.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140809264433---1564954080.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/toxuzabapujakolumur.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16145ad334d02f---bolakoxatexonega.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/39244911912.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_off0000b26a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB26A 10528 bytes
SHA-256: 44b61cae2f9242e1c0a8a43d58e5cc99427a977720e4331d824cc996cdf09f32
font_01_sfnt_off0000ca62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE274 16596 bytes
SHA-256: aa46261aa4fcd8f0ab0c4bdd7689d7757fada5aa9576f6a3f98159baa8578c48