Malicious PDF — malware analysis report

Static analysis result for SHA-256 819cbf57fd0bd6ae…

MALICIOUS

PDF

73.2 KB Created: 2021-03-20 01:44:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6e21eae150885c1ec7887839b83a4010 SHA-1: b942aafe441ec2bbb77e652ca03bb85ea2a3ae4a SHA-256: 819cbf57fd0bd6aee4405a636b927357f51ffcafb93a925a30a2b72814ed267a
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to SEO-optimized PDF files hosted on various domains. This pattern is indicative of a link farm or a phishing campaign designed to direct users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://botokaw.ru/wix?keyword=ccsd+maintenance+gillette+wy
    • https://cdn.sqhk.co/vibifexode/IjezR6P/adversary_definition_synonyms_and_antonyms.pdf
    • https://static.s123-cdn-static.com/uploads/4369161/normal_60074c4707132.pdf
    • https://cdn.sqhk.co/buzomesil/eCgePQO/xipurugepewoxutasupavab.pdf
    • https://cdn-cms.f-static.net/uploads/4365546/normal_604e7bea621de.pdf
    • https://cdn.sqhk.co/luwanuriwaba/iggSstx/best_dwarf_legendary_lords_mortal_empires.pdf
    • http://xapizokawe.iblogger.org/categories_of_biomedical_waste.pdf
    • https://cdn.sqhk.co/gakilofod/eTE6igz/radenazozowakutunepe.pdf
    • http://xiluzoxasefeb.iblogger.org/easy_boogie_woogie_piano_sheet.pdf
    • https://cdn-cms.f-static.net/uploads/4372085/normal_604009e15a1cb.pdf
    • https://cdn-cms.f-static.net/uploads/4409614/normal_6034d647d295c.pdf
    • https://cdn-cms.f-static.net/uploads/4444644/normal_602ad77a4ffee.pdf
    • https://cdn.sqhk.co/rowunozimop/vha6xmQ/spectacle_lake_beach.pdf
    • https://cdn.sqhk.co/jaziwuke/Yjh2Hqq/82425749548.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://e5720c39-3c1c-4a52-9be9-509675281b5a.filesusr.com/ugd/0010c8_af91641fe3264597afb05d671302df8c.pdf?index=true
    • https://0306adf0-382e-42f1-903d-71c3961c97f1.filesusr.com/ugd/7ff653_284e64639bbd422a9ea142faac378bf6.pdf?index=true
    • 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_off0000de99.bin
3901806a613021076f075c5e0a296bc8d17fc133df76c3f2d48f52f41a9ea6c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE99 5264 bytes
font_01_sfnt_off0000f07b.bin
22e9cf93414a52441a0bcc607c5c659e2072f645a7d239f7f22c9ff26548f2fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF07B 11508 bytes