Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7b4535bb6bfe1ad…

MALICIOUS

PDF

66.8 KB Created: 2020-12-15 20:45:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7a92d7b194e50e0b1853f70742bd86e6 SHA-1: fad14a2d3c969b2dd5a934c692d94e805e95a63e SHA-256: b7b4535bb6bfe1ad7a97305e4a10381b7240c62abedb7a715c00a17f8b541d41
184 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm used for SEO manipulation or phishing. The ClamAV detection and ML classifier indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs and the heuristic findings point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8092

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
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://traffset.ru/strik?utm_term=chemistry+chapter+8+and+9+study+guide+answers
    • https://rikurifijuse.weebly.com/uploads/1/3/4/6/134681474/2743582.pdf
    • https://putojedenavaxo.weebly.com/uploads/1/3/2/6/132683165/wirozux-xexowifotuguru-legugujasuwolam-binawo.pdf
    • https://sujajikozodes.weebly.com/uploads/1/3/1/3/131384638/10fe2ead0b53.pdf
    • https://dujikofuzi.weebly.com/uploads/1/3/4/6/134610135/gisupakes.pdf
    • https://dejolezeg.weebly.com/uploads/1/3/2/8/132815968/e06be.pdf
    • https://jaweditulopo.weebly.com/uploads/1/3/4/3/134313576/dajuzukumo.pdf
    • https://xotoxagat.weebly.com/uploads/1/3/4/7/134753993/gasufanevulu.pdf
    • https://cdn-cms.f-static.net/uploads/4530937/normal_5fd7d1f617916.pdf
    • https://tivakoxidedopa.weebly.com/uploads/1/3/0/7/130776298/6981840.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/f4178fb2-2f39-48c4-a1d6-8b80b444deeb/ogre_battle_64_chaos_frame_guide.pdf
    • https://uploads.strikinglycdn.com/files/fe29bb6f-664c-4a68-be2d-9ed36e185e8c/zikunigizebexajaf.pdf
    • https://s3.amazonaws.com/dazutun/girl_guides_of_canada_registration_bc.pdf
    • https://s3.amazonaws.com/dovulavavo/26290589930.pdf
    • https://s3.amazonaws.com/xanofamaja/xusajif.pdf
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d627.bin
0a2042a34a3d81df781787627815993ca1536900c1426e1e8750f848e375a93f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD627 5904 bytes
font_01_sfnt_off0000ea22.bin
7e6f0c0eb133219f9c513dd6a741878ffe069156895073dc0840f72785b3a8ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA22 10348 bytes