Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c737c788c4d1e0a…

MALICIOUS

PDF

66.4 KB Created: 2020-11-26 01:31:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8447357cf4a19b0b18b57de734d37d61 SHA-1: 7c293823c68cd879f1222c51408df46617dbea6e SHA-256: 4c737c788c4d1e0ab56db7e76c57c3dd041624d86888c4a9ecc9ae7cf4617cdf
156 Risk Score

Malware Insights

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

The PDF contains heuristics indicating it is a link farm and has been flagged by ML classifiers and ClamAV as malicious. It embeds external URIs, including one pointing to 'trafffe.ru', which is likely part of a phishing or malware distribution scheme. The document body, though heavily obfuscated, suggests a lure related to game cheats.

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://trafffe.ru/123?utm_term=cheat+best+fiends+forever+apk
    • https://cdn-cms.f-static.net/uploads/4383924/normal_5f8c68e5248c5.pdf
    • https://cdn-cms.f-static.net/uploads/4373264/normal_5fb2d796b07b2.pdf
    • https://cdn-cms.f-static.net/uploads/4413458/normal_5f9487d018471.pdf
    • https://mazegiwekode.weebly.com/uploads/1/3/4/5/134529082/f0dd66259c13fdb.pdf
    • https://bameveba.weebly.com/uploads/1/3/4/1/134108569/7044481.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/6044a32a-c61a-4815-844e-fde774ba83a2/17861956111.pdf
    • https://uploads.strikinglycdn.com/files/bc7b66ab-b775-4cbd-8583-be7eaf3719b3/lijurak.pdf
    • https://s3.amazonaws.com/dowavelaxam/26387303087.pdf
    • https://s3.amazonaws.com/mulerux/assured_shorthold_tenancy_notice_form.pdf
    • https://s3.amazonaws.com/liguwubore/temporal_difference_learning.pdf
    • https://uploads.strikinglycdn.com/files/0d194ead-5ab9-4282-a3c7-a664de9cd46e/2014_jetta_sportwagen_tdi.pdf
    • https://s3.amazonaws.com/lekizopiloref/13797559655.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_off0000c73e.bin
dd74bcf7508f96c9bf704e23acf430f37897640b2fecb6f58888d42ea72ce95c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC73E 5264 bytes
font_01_sfnt_off0000d916.bin
3a7066d23c37b3d9611b08f54a8287f7f5f0043429533c6ca596b32fd0f81e9d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD916 10592 bytes