Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcba6ac6af46b152…

MALICIOUS

PDF

72.7 KB Created: 2021-02-17 18:46:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 34acd2e2a0d9f170a8bb3943a7fa85ee SHA-1: 7e3c57676ef6bac364cfa5ae4ffb0501663fe717 SHA-256: dcba6ac6af46b152e7813653d2028c26d993d785552f75e088efd036609c102f
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, flagged as a 'PDF_SEO_LINK_FARM', suggesting a tactic to generate traffic or distribute malware. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as 'Pdf.Phishing.Trojan'. While no scripts were explicitly extracted, the structure and heuristic firings point towards a phishing or link-farming attack pattern designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jacksth.ru/wix?keyword=worksheet+writing+ternary+formulas+answer+key
    • https://static.s123-cdn-static.com/uploads/4384482/normal_5fe5a3350ca0e.pdf
    • https://sijetuso.weebly.com/uploads/1/3/4/4/134499475/vigemuma.pdf
    • https://cdn.sqhk.co/pazaxefuma/NPiejdS/74608276.pdf
    • https://static.s123-cdn-static.com/uploads/4393353/normal_60010ae59149a.pdf
    • https://static.s123-cdn-static.com/uploads/4468296/normal_5fde41fc23344.pdf
    • https://cdn-cms.f-static.net/uploads/4470964/normal_601648e263150.pdf
    • http://vijuziruzunubiz.iblogger.org/mofuz.pdf
    • https://cdn.sqhk.co/jujuziwe/f97ijPI/nuremipuzudiwijesazorivup.pdf
    • https://static.s123-cdn-static.com/uploads/4528876/normal_5fc6cc6a3605e.pdf
    • https://fukopimuwevi.weebly.com/uploads/1/3/5/3/135351499/2260383.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/nowonovege/breville_espresso_oracle_manual.pdf
    • https://s3.amazonaws.com/setikizo/yalova_zel_atakent_hastanesi_i_bavuru_formu.pdf
    • https://s3.amazonaws.com/gedimuta/large_format_camera_movements_explained.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_off0000deb9.bin
c76aa63eac15bc07b96263a1ec8adb760595c9ee8f2fe4917eecd03e05145531
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB9 5452 bytes
font_01_sfnt_off0000f13f.bin
62193dffa60cca49f9d57e12a9304a6f5b03b66433b7431c98d47045cd2d1fee
pdf-font-stream PDF embedded font (sfnt) at offset 0xF13F 10548 bytes