Malicious PDF — malware analysis report

Static analysis result for SHA-256 18541e1ad44ba79a…

MALICIOUS

PDF

78.4 KB Created: 2021-04-29 02:54:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 0293f61bd406883a0c5c511ac99424cd SHA-1: df4e7bb7c2b8a201b2f9324b44cb2ee5b5e2b45c SHA-256: 18541e1ad44ba79a33dd5b70058c1897928007d9516345958a1089c4d9b68e7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites, suggesting a link farm used for distributing malicious content or phishing. The presence of embedded URLs and the nature of the heuristics strongly suggest this PDF is designed to redirect users to potentially harmful external sites.

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 http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/sqrnpo5ob5iiaq4qgu3dvpgt34/59276917642.pdf In PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608037f87b037---49802448804.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7d78292c3---nifogukejinubugazabenen.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/5e624636364085e344cb2b980a73fb14/1888166096.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160871931de26f---gaver.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16078aaae573b0---25608966943.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/6f0f77492e25491136d3c2b02f3765cf/29797662870.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1a71690ba---zevisumekipu.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e193966a16---15015619849.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607698440af3d---vofosovod.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/2v2jkaftemg3mdo0qd4hg2csl6/32269938327.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/04a1b93e52de4e1536d3cfe69acc6edb/mexenugijomizuxa.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/ca200367f6bad374ab11d5de175c4388/28290011682.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607972e1e6b79---21627984732.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/YTWXjIUwRh0/uplcv?utm_term=cardiac+arrest+australian+guidelinesPDF 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_off0000f885.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF885 5012 bytes
SHA-256: 99f43232932f0dec16d3415fe6b8a6d8e29ba2f6fb9457ab1ff8f4711e8e7435
font_01_sfnt_off0001099a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1099A 10268 bytes
SHA-256: d890f977bd4e41c2075516a710891cf98cbb4b45afc9487aa62fa8dbbfb65764