Malicious PDF — malware analysis report

Static analysis result for SHA-256 55416b4b0b1b74ff…

MALICIOUS

PDF

85.4 KB Created: 2021-07-01 22:58:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 952386abf9a1994ea38a9d31aa3299c1 SHA-1: 87e5bf7501b447d04c943be03ea014d953e4a665 SHA-256: 55416b4b0b1b74ffc6ffc8c6633f59711f180a2c9866dab4c685fe2b2ea173c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious campaign, likely involving redirection to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://coretry.ru/uplcv?utm_term=candice+great+british+baking+show
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087f90fdb843---39100924411.pdf
    • http://aircond.md/upload_fck/file/13045088627.pdf
    • http://sushikyototogo.com/uploads/files/likida.pdf
    • http://bluedevils59.com/clients/862365/File/nexarope.pdf
    • https://aokman-drive.com/d/files/mixagobesodute.pdf
    • http://malagi.pl/user-files/fck/file/nenafuvanuwekesagupas.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/7f35360180b2be5bb0ebb831d5e5fda0/lolivuxeno.pdf
    • https://tenekedjieva.com/uploads/file/55696878984.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16099d8becd55b---65915166461.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bda3b07f156---42514677604.pdf
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/14668643738.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aab288d507c---83997401144.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608fac2c2e363---kesokumepobezonorejar.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/snpdb0k8vlogauul2pvhh22e30/lejarudibi.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbe08ca29d---wirujomomavijofiwuveb.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa171cf416---63089822340.pdf
    • http://studioindelicato.com/userfiles/files/84821402264.pdf
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b867d32ee78---99914241945.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c12c7509c2---31375368038.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/b24e4040b62fe2842c7c4ac1897ef41e/19917700133.pdf
    • http://phuvuongcorp.com/luutru/files/leturugazox.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081298ae2d28---gixorajujosiwune.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7b8.bin
e2333f78915cc7e70903419b55eaa3976c045c7b4d0e9574ea526c03b5303d28
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7B8 10952 bytes
font_01_sfnt_off000100f6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100F6 16792 bytes
font_02_sfnt_off00011908.bin
7dd6ad087ae56827f85521963b5b135f3cd112b41eddb29e90adc3fcc38f6d79
pdf-font-stream PDF embedded font (sfnt) at offset 0x11908 18120 bytes