Malicious PDF — malware analysis report

Static analysis result for SHA-256 1aff23da7a16cd07…

MALICIOUS

PDF

82.6 KB Created: 2021-06-25 13:58:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 2e1a4cfe6c33c702f1a4ef5ad3b77e61 SHA-1: f72347a98806f3c2e28bb95122dffecca2d907bb SHA-256: 1aff23da7a16cd076a3c6c58b12a04fbae3e5eca73a5c086f508e701f687ae25
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to exploit users via a compromised CMS upload, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://medvor.ru/uplcv?utm_term=normal+heart+rate+for+9+year+old+girl PDF link annotation
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608362252723b---69896373821.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b46c6ad227---pavoxuforoxud.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/90209067194.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/bulazalelorosaragupof.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0ea00ba24---39785896806.pdfIn PDF document text
    • http://valleypainclinic.org/userfiles/file/nupikegipifuditisewufaruj.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/viraduxuxomimexapuvuliti.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/9855337338.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/hrol6rvh52m7bf07kgo1i4r135/zuguwewadetekimi.pdfIn PDF document text
    • http://greenbiotech.vn/uploads/userfiles/file/91673634791.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ac6e5772a---58235272071.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/81524601288.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d24c75d619d---vuzufijizalujamakomilem.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/xixesovolikelipebaxuv.pdfIn PDF document text
    • http://zonwering-belgie.com/ckfinder/userfiles/files/98749158775.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/qo565hksaid6fjjtkv4o3so10q/vozelifugokikosutev.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_off0000e0bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BD 10788 bytes
SHA-256: a8a6b8df122a751a8b7a22a50b638094617ef27578c3618b790334bd88a86281
font_01_sfnt_off0000f965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF965 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011177.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11177 17084 bytes
SHA-256: 778aef8d372dcb7ebda01ffa092b3ab7cafda8d9f89e9592e88545400b46755a