Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7efcf52622390f8…

MALICIOUS

PDF

70.4 KB Created: 2020-11-26 10:20:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: efe50eb91b8bcc677247b87e923d9f24 SHA-1: 1da2908375ec434f71213defa59259a6ef89cfa3 SHA-256: c7efcf52622390f8563ccd728f4f0fa58220e6997a9bf7cf88e5e0c18bb3555b
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a 'link farm', suggesting a malicious intent to manipulate search engine results or redirect users to potentially harmful sites. The ClamAV detection and ML classifier strongly indicate malicious content, specifically a phishing or trojan variant. While no scripts were explicitly extracted, the PDF structure and extensive external linking are indicative of malicious activity, likely involving the exploitation of PDF vulnerabilities or social engineering to drive traffic to malicious domains.

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/123?utm_term=oracle+12c+architecture+diagram+and+explanation+pdf
    • https://cdn-cms.f-static.net/uploads/4368469/normal_5fa8c91eaa323.pdf
    • https://wanuwoziburake.weebly.com/uploads/1/3/4/4/134458428/7948983.pdf
    • https://cdn-cms.f-static.net/uploads/4413693/normal_5fa5defe346e1.pdf
    • https://cdn-cms.f-static.net/uploads/4393790/normal_5fb5443d8b4cf.pdf
    • https://cdn-cms.f-static.net/uploads/4373769/normal_5f91b7c387518.pdf
    • https://jesezexesupozor.weebly.com/uploads/1/3/4/6/134623998/875c294.pdf
    • https://cdn-cms.f-static.net/uploads/4381988/normal_5f9bde63a4d5c.pdf
    • https://cdn-cms.f-static.net/uploads/4471455/normal_5fbb0578cae63.pdf
    • https://cdn-cms.f-static.net/uploads/4370299/normal_5f8aa6e68d5d7.pdf
    • https://timokejega.weebly.com/uploads/1/3/4/4/134454798/6203713.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/4fc3641e-3980-49f8-88dc-0f0378e69fbc/gumeg.pdf
    • https://s3.amazonaws.com/tunenijexe/21042208928.pdf
    • https://uploads.strikinglycdn.com/files/a1dea644-ef16-4c90-b6bc-2323638b9480/89894085832.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_off0000d4b9.bin
ece57ff1fc60b4824021e70c45bcd5534bca8e1776bb87651ee6fa4c893213b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B9 5668 bytes
font_01_sfnt_off0000e7e0.bin
44c54be969ba6c95f89c62cb18938992d70848ee8d9fdb6c6d1de897c269cfac
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E0 10688 bytes