Malicious PDF — malware analysis report

Static analysis result for SHA-256 861ac274ec314888…

MALICIOUS

PDF

72.8 KB Created: 2021-04-29 11:35:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 433455046f40099b167166886cdad3e0 SHA-1: 7a23855443d4fd932efb201a0830bd200d15d913 SHA-256: 861ac274ec314888094baf79f3ff190f222209add3c4fa7905181b0193364b2e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites, directing users to various PDF files. The embedded URLs and the nature of the link farm suggest a phishing or malware distribution campaign, likely using a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f934d1e617d60c34009a0792cbf505f9/63238303870.pdf In PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/j27hcl3jcln5tn4knqitp1j3fd/fazorapemi.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/8a38bd1937d9ab6ef80cf9f5e9ae7f5b/nisagaritisegikageziwuv.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/6238bec30b80a1e1d7a8a9daaf9dd824/fesiverefow.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160729defabdb0---89370940867.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/a24c824392252c0f7cb0627cbff4fd1a/mivukikekowud.pdfIn PDF document text
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/96830092ce79d8d6f2125babe3d2b4b5/96511876221.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/a877e7e1544f41aef291f8d0bfc902cb/rawomusafidosujudofajot.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1608167c29618b---pumixanipijevezezowuvowep.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/80c16f9389be4b210b1181120a6b53c3/25100050318.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780fa7214fd---nekogokunemexak.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/196e7793d92c270043a0f3c45d36347a/69299685260.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607491ae8d372---dugodiladidaduda.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/deb6808f7c5df6edc7e5da5d749d65c5/rixekejudogunanukogawiz.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/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=baluta+marathi+book+pdfPDF 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_off0000de8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8F 5356 bytes
SHA-256: 94be637385b0d6cf9b157769f98bcbfd523018e565e831eb3430a3a09f342459
font_01_sfnt_off0000f097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF097 11684 bytes
SHA-256: feee57f1be15f5b0fef4909d7f03cef3317086245fbe5f23352216ce15cd06e1