Malicious PDF — malware analysis report

Static analysis result for SHA-256 d43aa35c958b8fae…

MALICIOUS

PDF

79.2 KB Created: 2021-06-19 11:56:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 828515a95a64d41711b6f2f0be4626f6 SHA-1: 8b2e2b02dae7eab674868ebfc7bbb29cd595afdb SHA-256: d43aa35c958b8fae671a0eaef9f217613936503de260429eebc06b8f084fe980
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://laborke.ru/uplcv?utm_term=the+fast+and+the+furious+9+full+movie+sub+indo PDF link annotation
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/d6d704de0a26b089b73280e8690021db/dugatuvawijefetas.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b75f4bcf4b---nuganinamivosogikunizo.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c62adf23250---ruvuvizefalebobirajeg.pdfIn PDF document text
    • https://soudurelausiere.ca/upload/editor/file/sejaga.pdfIn PDF document text
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/bilovovimokomoguwovo.pdfIn PDF document text
    • http://kevinmcallisterlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/74002448192.pdfIn PDF document text
    • https://wietsevoermans.nl/ckfinder/userfiles/files/92522004647.pdfIn PDF document text
    • http://flirdining.com/uploads/files/gojimibofanazi.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/754e9e15115a6357206d8aabea869be9/jivegaliwawoxitekajoduwig.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/69305457c4dff323e64acd621b702983/20069793551.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/43759029543.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/505cdb449945bc934d772003e6aa2593/90732886517.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/6fc200d78059edde53df7e3a2073a1a1/teninu.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a22991c26d0---wobexawatiwi.pdfIn PDF document text
    • http://educationexplosion.com/clients/a/aa/aae59ec6301d25964842a0067e0ae100/File/zegugupisefazebujez.pdfIn PDF document text
    • https://eberli-medical-supply.ch/upload/file/fujuxisaravakap.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7e08e8794---mutotenomutewak.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094793150b06---puxakor.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_off0000f379.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF379 5452 bytes
SHA-256: 4647e695d74cc4b785375b7ca68d6438a9e468ee2aead4a52c579aa6945f35e7
font_01_sfnt_off000105d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D9 11696 bytes
SHA-256: d8a50d2438b0624f2e1fb7959e5e714cddf971eacbb780f7da8c5f7cf71202bf