Malicious PDF — malware analysis report

Static analysis result for SHA-256 66b554983e5dd3d5…

MALICIOUS

PDF

84.9 KB Created: 2021-06-28 03:34:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 845f943f2530bd6dbc7514c4ca028c70 SHA-1: 5e7d5bd6d1f73485db289dbb4436e1c8d9adf966 SHA-256: 66b554983e5dd3d5857a248735063ee215ba8c7d3fcda2c0f2b45028c51b405f
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to numerous compromised WordPress sites and other disposable hosting, suggesting an attempt to distribute malicious content or phish users. The primary attack pattern involves directing users to external, potentially compromised, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://efrex.cz/files/file/47519921253.pdf In PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160877a9344e02---21542269907.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/26b6aed90be90397eb723099ce3d8d04/22422079743.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/j1ad0tm1c366jqvokis5rdk7g2/69217866062.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/dawinewuzenu.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/2f1r7ktvgchlgjml2ob7n8muf0/12168279818.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/57359047925.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/e427aeb9b4bb882e90bf68dd20d79238/83488079499.pdfIn PDF document text
    • http://targdenunti.ro/userfiles/file/viforilidanud.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/b70218c43d9a831fc78c0f31028257ff/98810412855.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/50s5vupcr1rs5sugrmalccpkfr/lovuwodejaxosibiluvo.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a97d8066ed3---xegojedolepowareboz.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/zizulebo.pdfIn PDF document text
    • http://mawaevents.com/uploads/file/bagemakunom.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/f04bc723a2982554c1d9bcf83252d40f/3541913271.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/97d5e6fb632ceec9ce0fb9056a4fca8e/fidolu.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/81n1eetn4i4oljhk3i8af6najh/gegugiwojefukevapogufoleb.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/53043471368.pdfIn PDF document text
    • http://kompletucetnictvi.cz/files/file/vavoson.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/ji6mm7hn1p432ck2112p4pbbd2/movixidimajimakafupuzuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=colombian+red+fin+tetraPDF 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_off0000ea45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA45 17216 bytes
SHA-256: a1dcf3905b9a905cc30e39d1ad3ab3b4d991d2703b5006239712966d8ed4866d
font_01_sfnt_off000116f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116F0 10516 bytes
SHA-256: 7531e844cca05ad7a54e084d1928d07251e6391f497628a0062c4d8f18761be9
font_02_sfnt_off00012ed3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ED3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1