Malicious PDF — malware analysis report

Static analysis result for SHA-256 520ba4f6255409b2…

MALICIOUS

PDF

87.2 KB Created: 2021-08-24 17:33:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d76697d9e16161da87c5f3e5ba84fe1e SHA-1: f203f1f32db47667162dde26b6f53a4c4731b8cc SHA-256: 520ba4f6255409b23b8daad0050483f3e43fc7620ba657d2bf6ec796910b1480
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised CMS upload storage and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The embedded URLs, while some are marked benign, contribute to the overall pattern of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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 http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/731673d3a6b3c4cc8911c76815ec1cf3/48590401669.pdf In PDF document text
    • http://a-mega.ua/images/uploads/file/58352779100.pdfIn PDF document text
    • http://technoculture.cz/admin/upload/file/34316727601.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16094407b17dcd---sedorubakofefopuda.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/koposefuzajopedodanoba.pdfIn PDF document text
    • https://bucatariizidite.ro/printuri-fi/files/dufuzaliperuk.pdfIn PDF document text
    • http://giadinhlaurenso.org/upload/files/pamupofalidimadug.pdfIn PDF document text
    • http://mispuntossaga.com/campannas/file/gizir.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/4a0571eddad9480242675334ebc4b60e/kewatawa.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcac361821---22881415025.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16086293b8cd96---wixolekamudotaredolunix.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/53687892681.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210629222748_0y7v9p.pdfIn PDF document text
    • http://unicaconsultoriarh.com/images/files/19813485114.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16082219e886da---bunaxime.pdfIn PDF document text
    • http://soupworld.de/upload/file/96120554850.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/37898108695.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/zejemikojifugagakokugiv.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/idmrd89p3r65de1hj9udna0kg6/judubizasefebobobotu.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/061ea855087e846bd1ca7846c00a6aed/91728880199.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/daxedejuzaxoje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=having+a+blast+meaningPDF 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_off0000efc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC3 17728 bytes
SHA-256: 65881cc56b318fb915d2c149cc949ef8934f85fddcb9221643c3eced7e857205
font_01_sfnt_off00011dd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DD8 10428 bytes
SHA-256: ac2ff37e54b959fd85b5ec7dacd9aaaf2c3d72c0bf0ef0b9fa3816ef67c00ac8
font_02_sfnt_off00013573.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13573 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1