Malicious PDF — malware analysis report

Static analysis result for SHA-256 937d715d09ebc62b…

MALICIOUS

PDF

70.1 KB Created: 2021-06-08 01:08:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: cf30647b116876aeac4fd1d3dfe2560d SHA-1: 4b9b36ed8c51613898aa1b867c5fa5d0a36b5b92 SHA-256: 937d715d09ebc62b02dac91e98b4b7bc2224edb25042890f4a7e995f109deff2
156 Risk Score

Malware Insights

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

This PDF document is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, presenting a deceptive educational topic to mask numerous links pointing to compromised WordPress sites and disposable hosting. These links are likely used to distribute further malware or conduct phishing attacks.

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://nomylo.ru/uplcv?utm_term=ejercicios+de+problemas+matematicos+resueltos+para+primaria PDF link annotation
    • http://www.gabrielamaciel.net/images/content/file/favalozuterumunubufubizo.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607854ad9336d---92680688867.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfa3d2f8c7---womomiropaluj.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/12188586430.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160be8f4a57263---88110284599.pdfIn PDF document text
    • http://ghioroiu.ro/sites/default/files/file/2481814174.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aca1a122f34---30129753386.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160703b14d1cd3---73161804026.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/cecdg0vht8sb3dkq2vuaivms6i/rakonujakobizawokijizove.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087c10a8db11---winido.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/e5d055b40478c036bb05de67ce9b6306/vabenutasu.pdfIn PDF document text
    • http://xn--h49avwqct32ewe967crscpsaz7d.com/ckupload/files/75709487137.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607971946f134---46456903293.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/dovopigasazanuzupetu.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/dcb96acfeca184d1e53f6efd50e1a522/35313766816.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD039 5392 bytes
SHA-256: 732ff5f1f8ba7517c3533aeedf5fa4a240cd970e3461016f720f1172060e3fef
font_01_sfnt_off0000e272.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE272 12200 bytes
SHA-256: d9301cd0d08d89443341c067f18a89a3733c4948f11959b2c1f48d72844ab8e9