Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9ebb9da1c1dc532…

MALICIOUS

PDF

68.8 KB Created: 2020-11-26 00:48:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fecc7ca21956139567509790abc2db98 SHA-1: 4e8f357fc2fd344cddb2db90870a8a5893ab1c8a SHA-256: d9ebb9da1c1dc532594fc186192c51fb1f99fd455735e13a961436e8f848f0d2
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a large number of external links, identified as a 'link farm', suggesting a phishing or SEO manipulation scheme. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards an attempt 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://traffnew.ru/123?utm_term=henle+first+year+latin+pdf
    • https://cdn-cms.f-static.net/uploads/4446287/normal_5fbed5ed6eaea.pdf
    • https://keniwuki.weebly.com/uploads/1/3/1/4/131483234/mikukinib.pdf
    • https://dineretisa.weebly.com/uploads/1/3/4/7/134709889/zisokukitevuriti.pdf
    • https://cdn-cms.f-static.net/uploads/4403271/normal_5fa024011dd9d.pdf
    • https://tenasusuboziwid.weebly.com/uploads/1/3/4/3/134349012/badowupogurute.pdf
    • https://cdn-cms.f-static.net/uploads/4417670/normal_5f9cdd962e88d.pdf
    • https://cdn-cms.f-static.net/uploads/4380525/normal_5f9389b3da738.pdf
    • https://cdn-cms.f-static.net/uploads/4411916/normal_5fa8befa2cbf7.pdf
    • https://mexugagerow.weebly.com/uploads/1/3/4/4/134482965/jawogoxip-podular-jurozirafelabev.pdf
    • https://cdn-cms.f-static.net/uploads/4368493/normal_5f982640bdb7d.pdf
    • https://cdn-cms.f-static.net/uploads/4374857/normal_5fad6c02d04d6.pdf
    • https://robonodibogiva.weebly.com/uploads/1/3/4/6/134630072/redadepis-zisawir-bodosemetobunej.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/nonabafat/first_order_kinetics_drug_elimination.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c622.bin
ff122ac81af548c41f6f0de925cde81cb2467746976754f8cc5e2deab4fe4f53
pdf-font-stream PDF embedded font (sfnt) at offset 0xC622 4776 bytes
font_01_sfnt_off0000d661.bin
f49feafe67bcdaaf8f33e166a4fc742a392a39df6fc2dca32028b51da81e13ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xD661 9836 bytes
font_02_sfnt_off0000f80e.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF80E 4324 bytes