Malicious PDF — malware analysis report

Static analysis result for SHA-256 e431e81463e6e158…

MALICIOUS

PDF

72.8 KB Created: 2021-05-26 02:34:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: b3d344564d664d4a64bae813d75c983e SHA-1: cdcebbae00361914dbb3371c049c3eec836a972e SHA-256: e431e81463e6e15846c53dddb34d97333df772468ba6fe6b0074733e35eaff7b
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress upload directories, suggesting an attempt to distribute malicious content or phish users. The presence of numerous distinct hosts hosting similar PDF files indicates a coordinated effort.

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://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ebff165be---87820881737.pdf In PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609114ce6da2c---zerabonekalejijafip.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/9acf681ba919713277a96c219aef19db/doxegezip.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/9d4ed65b3904681d4a5963a3b69d8d2e/lutowivuxoguputales.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160958326a7885---vulajitibamuremazujedak.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e4beda59e---dekusaj.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096def13cc88---tipamuluxasamomupagejanu.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/ipavpd5ed6tv3jr9t7iqc98tvt/18304706927.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832404b909a---nujexetebenunajuvovikus.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c37ff82e11---zikimesukodevupofijuwor.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/e58b2736c324392ac77af7a4cc163bc7/71622158145.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e48d56120---sefadofidugasipipo.pdfIn PDF document text
    • https://synersys.fr/contenu/file/61239570400.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/5e70e49e55a17dc3bde68539721384c5/12728111374.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/begupuwerunudezoreziz.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/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=formal+and+informal+greetings+in+english+youtubePDF 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_off0000de02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE02 5516 bytes
SHA-256: 57c3fe8959f261de2ef0cd31a2be69428d419f328ca6b538f3957becc08f0014
font_01_sfnt_off0000f09d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09D 10400 bytes
SHA-256: b006c90645979808a6698bfbc1aab0ef31732fcf52e6e9b304d30a2ae1c76bd4