Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c838a1b374cea70…

MALICIOUS

PDF

61.2 KB Created: 2020-11-27 09:32:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d625ad846d91909329c4b4c12f14daa5 SHA-1: ec9efc0e9c41ec860ff31318067494496bd65762 SHA-256: 4c838a1b374cea70140f353c65b8ad2a1313d7888862d0afff32bf03a1630f87
214 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, with several pointing to known malicious redirectors and forming a link farm. This indicates a likely phishing or spam campaign designed to lure users to malicious sites. ClamAV detection and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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://traffmen.ru/aws?utm_term=joe+mettle+turning+around+for+me
    • https://cdn-cms.f-static.net/uploads/4426812/normal_5fbb2d9327d9e.pdf
    • https://cdn-cms.f-static.net/uploads/4450355/normal_5fa8bab339132.pdf
    • https://cdn-cms.f-static.net/uploads/4366947/normal_5f99e13467de3.pdf
    • https://gezeteweni.weebly.com/uploads/1/3/4/0/134040803/8c7d6d.pdf
    • https://cdn-cms.f-static.net/uploads/4425227/normal_5f9ee4fb12c60.pdf
    • https://junovolosexev.weebly.com/uploads/1/3/4/4/134467690/f8d9e2507d6fb.pdf
    • https://cdn-cms.f-static.net/uploads/4366302/normal_5f87a164b8de8.pdf
    • https://cdn-cms.f-static.net/uploads/4372735/normal_5f88ae9e13809.pdf
    • https://cdn-cms.f-static.net/uploads/4381289/normal_5fa688baaeb5c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/mefadedosuw/architectural_design_concept_examples.pdf
    • https://s3.amazonaws.com/davawina/civil_engineering_reference_manual_16th.pdf
    • https://s3.amazonaws.com/dabatisew/kezizawarojefinedas.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_off0000b32d.bin
881096c8701d2e3c48c0d68098df54ef29f9f4e57c8fddf760b277b8d4bcf3cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xB32D 5036 bytes
font_01_sfnt_off0000c437.bin
30ef7532f08fc1d88d79fef1cf5609a3fdbb3aee9e06f615d17b67539e331821
pdf-font-stream PDF embedded font (sfnt) at offset 0xC437 10092 bytes