Malicious PDF — malware analysis report

Static analysis result for SHA-256 25a5c1bcb3eb4c4c…

MALICIOUS

PDF

73.3 KB Created: 2020-11-17 21:28:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6686dfcda94b3139699e4806c5b3f148 SHA-1: 6da51fb6dcce163a9526b993eb24f5d459c242bf SHA-256: 25a5c1bcb3eb4c4c721642b1e9c0858bc52ea31672f81c3e9c885e59729b0a47
156 Risk Score

Malware Insights

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

The PDF file contains a heuristic firing for a PDF link farm, indicating it hosts numerous external links. One of these links, 'https://trafftec.ru/strik?utm_term=a+midsummer+night%2527s+dream+literature', is directly referenced. The presence of a ClamAV detection and a high ML score further support its malicious nature. While no scripts were explicitly extracted, the PDF structure and link farm heuristic suggest an attempt to redirect users to potentially malicious sites, aligning with phishing or content distribution tactics.

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://trafftec.ru/strik?utm_term=a+midsummer+night%2527s+dream+literature
    • https://cdn-cms.f-static.net/uploads/4418963/normal_5fb29ec94b342.pdf
    • https://cdn-cms.f-static.net/uploads/4408464/normal_5fb2b8836e943.pdf
    • https://cdn-cms.f-static.net/uploads/4377912/normal_5f9aba16d57bd.pdf
    • https://butebipibib.weebly.com/uploads/1/3/4/2/134265815/3640087.pdf
    • https://cdn-cms.f-static.net/uploads/4409604/normal_5fb375ed62313.pdf
    • https://cdn-cms.f-static.net/uploads/4417306/normal_5fae39469c4ec.pdf
    • https://cdn-cms.f-static.net/uploads/4386081/normal_5f9c3b868b406.pdf
    • https://cdn-cms.f-static.net/uploads/4381320/normal_5fa1d011e2bbb.pdf
    • https://cdn-cms.f-static.net/uploads/4366982/normal_5f90d335d798f.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/wizedumi/gegefarolivemetux.pdf
    • https://s3.amazonaws.com/pukiza/disogolububizekolimari.pdf
    • https://s3.amazonaws.com/fasanag/24208967714.pdf
    • https://s3.amazonaws.com/duzexefemosaxe/unpack_dark_souls_for_modding_remastered.pdf
    • https://s3.amazonaws.com/bulikowexunepov/tijewe.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_off0000e3a3.bin
8203d294d23bfc221430767204171fe4240439e8aa023515ae5d280ea6fad73b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A3 5260 bytes
font_01_sfnt_off0000f55d.bin
978a539fb3f6bad58ed732265ba1f018e114c381d79ceac7be43a35c45896583
pdf-font-stream PDF embedded font (sfnt) at offset 0xF55D 10192 bytes