Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e231dc61b568c1b…

MALICIOUS

PDF

75.9 KB Created: 2021-06-13 12:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: e8ac8f3e00769d6099947aa73c669d99 SHA-1: d4c2de71e55f4e9e35f1dc5f705e11529082095f SHA-256: 3e231dc61b568c1bfde760a4c9f64cbd4566df2b9efb5a629c2dddeffcd56fa8
156 Risk Score

Malware Insights

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

The PDF file is detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links pointing to compromised websites, suggesting a link farm used to distribute malicious content. The document body, though heavily obfuscated, appears to be a lure for academic material, likely to trick users into downloading further malware.

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://pistant.ru/uplcv?utm_term=lakshmi+seshadri+obstetrics+pdf+free+download PDF link annotation
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c116d4a27ac---neruvoxojawikupekifubunej.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b52658b6b36---wemozurorunubukakoxof.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16088becc1ebb7---26783501588.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609be61bd40c9---22130472646.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/26ebc1c2bc57e941b66c1d3f36ec0ae8/nekewe.pdfIn PDF document text
    • https://elbag.net/wp-content/plugins/super-forms/uploads/php/files/1af659b14b000605421b7a00d7e0935e/8532265050.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/1a7d6e4352bde82048dfab619f54c9be/50055354026.pdfIn PDF document text
    • http://globeksa.com/ckfinder/userfiles/files/20559420299.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/43054299500.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/61814628114.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/nifazopurijuvovaka.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16080d9191aa10---naxopezobijuvaruralif.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/bfa5db5b545ddeb9a193da2d23b61366/44047038200.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/4bfd15b31333ac4a5f7a763a5cddaa5e/wopibixafojo.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6260be6c2a---36349187815.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160aff6d01d9f1---mazavifuxuwububovevake.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_off0000eb0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB0F 5632 bytes
SHA-256: ea90686a3db81f1ebf41a6d6a8bb3a0fd990c42fae1efeb2e544a4594f816295
font_01_sfnt_off0000fe22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE22 10456 bytes
SHA-256: 419beaa7235e4dcfc23f856d9d1261ebe5c4c6ce4e8260fdfb80913e2f1a66c8