Malicious PDF — malware analysis report

Static analysis result for SHA-256 86f73b195fae3c23…

MALICIOUS

PDF

61.2 KB Created: 2020-11-22 18:18:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 108b9006db4534521aa607a5c48926e4 SHA-1: 1aeebe26707cd1c60389510836a022e2de41c34d SHA-256: 86f73b195fae3c23636860f37fed1131dc07af5b157309e3756201d6e383b68b
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing or malware distribution lure. It contains a large number of external links, many pointing to PDF files hosted on file-sharing services, suggesting a link farm or redirection mechanism. The primary URL, 'https://traffnew.ru/123?utm_term=solving+equations+by+substitution+worksheet', indicates a potential attempt to disguise malicious content as educational material.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://traffnew.ru/123?utm_term=solving+equations+by+substitution+worksheet
    • https://panirosarukiza.weebly.com/uploads/1/3/4/1/134132539/a79b333d8bb2b.pdf
    • https://cdn-cms.f-static.net/uploads/4393514/normal_5fb3758c1a33e.pdf
    • https://dedaruxije.weebly.com/uploads/1/3/4/4/134455514/vikakituwisikuso.pdf
    • https://kiseridebajesa.weebly.com/uploads/1/3/1/4/131408791/baxojekibikelenugajo.pdf
    • https://cdn-cms.f-static.net/uploads/4368999/normal_5f88ceda1e717.pdf
    • https://judunelikirolo.weebly.com/uploads/1/3/4/3/134375477/365828.pdf
    • https://cdn-cms.f-static.net/uploads/4390051/normal_5fa57e254708e.pdf
    • https://cdn-cms.f-static.net/uploads/4385421/normal_5fb7d17853013.pdf
    • https://cdn-cms.f-static.net/uploads/4413578/normal_5fb3773cb9215.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/b6303f22-0925-4852-a7d4-4e4ccbc50270/purineniwabaz.pdf
    • https://uploads.strikinglycdn.com/files/20cf80e8-cb85-4f4c-9221-864324a20a2e/kagoxilonu.pdf
    • https://uploads.strikinglycdn.com/files/6d0a48af-66bf-4e10-b3fe-151668caf834/87797717270.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b345.bin
878a59317bf1b4d0ed75b99c86ccd814ad409b2d6d78a9e81dee1482c1e935ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xB345 5636 bytes
font_01_sfnt_off0000c688.bin
dcfc85751115865fd5ae3b8a879b9e66c299420e5796d95d6ace09398c089529
pdf-font-stream PDF embedded font (sfnt) at offset 0xC688 9644 bytes