Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bbfcbf86eeae93d…

MALICIOUS

PDF

91.4 KB Created: 2021-06-15 12:04:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6e396e75446bc023c32fd4efe428db93 SHA-1: 8dd3ba6f71e3a11e4441987ad6096ee5214de8a8 SHA-256: 9bbfcbf86eeae93d91929664a12b46d576069661d99859945af4a5422f1f3c20
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress instances, suggesting a phishing or malware distribution campaign. The document body, though obfuscated, appears to be a lure related to 'nuclear equations worksheet answers', aiming to trick users into clicking malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=nuclear+equations+worksheet+answers PDF link annotation
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/kordrf2qicj9ls7pkh4moop3d7/jujokutepero.pdfIn PDF document text
    • http://cokhixnktientien.com/Images_upload/files/18003370502.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a358ce009ea---48881414018.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/55495997558a520053dfdd9c48b17073/norinurodoro.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/36029351640.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/79909950032.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607846cc458df---kuvuduzakanatozedujadawin.pdfIn PDF document text
    • https://marmarases.com/upload/ckfinder/files/12101322542.pdfIn PDF document text
    • https://soechi.id/userfiles/file/sifulam.pdfIn PDF document text
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/5495cd6b0fc3b4227bc1d1fd98046367/vegiragukijogelo.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/q8n0bj7gj5l2b5iq6oqef8v0fc/75166700803.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/roaht1747mm0ahetep5ssmjklh/28307494060.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/58736484540.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/96476190570.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011a79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A79 5020 bytes
SHA-256: 4ece054b7fa6e4c33df16fa0cf19e32ec7e22362f596e449ca5b754e4292909e
font_01_sfnt_off00012b99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B99 11472 bytes
SHA-256: de477b308af464f59645b9583fde511024a194c7b45085a5ad3978474154757c
font_02_sfnt_off0001528d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1528D 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2