Malicious PDF — malware analysis report

Static analysis result for SHA-256 da4511dfbedd7c68…

MALICIOUS

PDF

68.3 KB Created: 2021-05-06 10:52:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 87f31b5ab508a05fd9e76c6a6e2a3cc9 SHA-1: 562107c5b9917d87047855b76383dba649fea688 SHA-256: da4511dfbedd7c684ad8412491d6f894ec7e97cc74411b00e7e584f3f4f5c721
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites utilizing form builder plugins for file uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body, though heavily obfuscated, appears to be a lure related to 'cause and effect'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d499ba4294---fuxelexujevatojebivi.pdf In PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607038bae8cfd---57659576430.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/5jhir24476aocl7iql77s7da24/jimepisulewapud.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8bbff0655---11063720732.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/f83a5024d6459ac92a1daeada9a6b484/zugasemafesuwa.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160916c7b6c106---56523340923.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092e1279f5ce---33728649309.pdfIn PDF document text
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/62a232c99bd69c9eaa6f7bbe790cc282/loguno.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/vil1i1nq2anlrb55ov4hcoetjk/88642625214.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/67730017336.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/f75f5e0d0b2d4819845b5a1528ff8735/11195516470.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607478b24beae---62967826758.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d3ffe45d0e---94544688967.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=cause+and+effect+example+paragraph+formPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD000 5540 bytes
SHA-256: 11c32e60fe312b77c04c2fa3caf647463bdfce767a1247d93468928d12b38215
font_01_sfnt_off0000e2af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2AF 10232 bytes
SHA-256: 64fd41a1543acca2102e8a6de51453980e4b08e0bbf6ee10e3130e071082f394