Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f5c52973c13e1ec…

MALICIOUS

PDF

93.1 KB Created: 2020-12-18 22:29:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2ca930e21fca8272ce2b15de4f655447 SHA-1: daff9ea154a8e11a577eb1761734e6cdb5f12690 SHA-256: 0f5c52973c13e1ec00a32c126917b5b8f574f07189e1ad3bee654215ac58e0dd
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, suggesting it is part of a link farm designed to redirect users to potentially harmful websites. The presence of embedded URLs and the heuristic 'PDF_SEO_LINK_FARM' strongly suggest this document is used for malicious redirection or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://trafffe.ru/strik?utm_term=botany+study+guide
    • https://cdn-cms.f-static.net/uploads/4466368/normal_5fbea56a7fa3d.pdf
    • https://cdn-cms.f-static.net/uploads/4366371/normal_5f985fa9420d4.pdf
    • https://static.s123-cdn-static.com/uploads/4489994/normal_5fc925fb866b8.pdf
    • https://cdn-cms.f-static.net/uploads/4458163/normal_5fa2ed501a3c7.pdf
    • https://cdn-cms.f-static.net/uploads/4471091/normal_5fd739c59d812.pdf
    • https://cdn-cms.f-static.net/uploads/4378165/normal_5fa52a9f68947.pdf
    • https://cdn-cms.f-static.net/uploads/4366401/normal_5f89d9cce2d1d.pdf
    • https://cdn-cms.f-static.net/uploads/4366980/normal_5f8871c48eac9.pdf
    • https://sibotapitagota.weebly.com/uploads/1/3/4/3/134378411/2155643.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static1.squarespace.com/static/5fbce344be7cfc36344e8aaf/t/5fbf67d07acac6192ab92ab2/1606379473107/critical_care_notes_clinical_pocket_guide_3rd_edition.pdf
    • https://s3.amazonaws.com/lopazura/bogeboxefitipibamo.pdf
    • https://s3.amazonaws.com/juzinaramip/mobusaxezevenametala.pdf
    • https://static1.squarespace.com/static/5fc78f50e9133927d90f8a19/t/5fd732fedf2f0204c250afdf/1607938814824/bajivejesajukagigazofoji.pdf
    • https://s3.amazonaws.com/megodipewukitoj/51689196253.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_off000131b1.bin
dd9fe4296a4e01d9eb510d6f71676d6fa0f23bfdbd4f2131ee85e563b50f475a
pdf-font-stream PDF embedded font (sfnt) at offset 0x131B1 5016 bytes
font_01_sfnt_off000142e1.bin
ecddf475cdabcc29da48346fcfd8b3343804d206d0aea6d02b045719e2413d30
pdf-font-stream PDF embedded font (sfnt) at offset 0x142E1 11132 bytes