Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a09921ff8258998…

MALICIOUS

PDF

65.8 KB Created: 2020-11-20 21:39:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b8814b325a7959ba7e7ea69e7d76eb93 SHA-1: da0a15c0a92b40d1b9565eafac04b720d8297c20 SHA-256: 5a09921ff82589980167e05b91b01c8ad2f55c4f0411c0018c370624d33b2d44
156 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, identified by the PDF_SEO_LINK_FARM heuristic, suggesting a link farm or phishing attempt. The ClamAV detection and ML classifier also indicate maliciousness. While no scripts were directly extracted, the presence of external URLs points towards an attempt to redirect users to potentially malicious sites.

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://trafficel.ru/123?utm_term=voxel+game+engine+reddit
    • https://cdn-cms.f-static.net/uploads/4379606/normal_5f8f444e51bf6.pdf
    • https://cdn-cms.f-static.net/uploads/4375908/normal_5f9949a8ea02c.pdf
    • https://cdn-cms.f-static.net/uploads/4376879/normal_5f9ab41260ba2.pdf
    • https://cdn-cms.f-static.net/uploads/4414851/normal_5f9dc0aa34375.pdf
    • https://wekijoborumotis.weebly.com/uploads/1/3/4/4/134484899/kimimufidunaw_gazusaxenunu_lulegu.pdf
    • https://saxibodusazo.weebly.com/uploads/1/3/0/7/130740440/4967626.pdf
    • https://cdn-cms.f-static.net/uploads/4368242/normal_5f9f3729292fe.pdf
    • https://cdn-cms.f-static.net/uploads/4382782/normal_5f9548ae9e014.pdf
    • https://cdn-cms.f-static.net/uploads/4426695/normal_5fb35cce4f5a4.pdf
    • https://cdn-cms.f-static.net/uploads/4379029/normal_5fa0808546c4c.pdf
    • https://cdn-cms.f-static.net/uploads/4369915/normal_5f8c6ae9b4755.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/lotibabakuj/dsst_substance_abuse_study_guide_instantcert.pdf
    • https://uploads.strikinglycdn.com/files/4bc7ef27-b035-4292-b764-de88ed017d09/78776713139.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_off0000c6c1.bin
922dc8c276632c4b4bfef88662fbff0e37edf13094e0bca191e6bade6c48d241
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C1 5000 bytes
font_01_sfnt_off0000d7b3.bin
8943d3e499c00ec27d0e6eaf98129b757c7d86b17c7007e9d74ecb951ac47c13
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B3 10260 bytes