Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c70c862e7fc698c…

MALICIOUS

PDF

71.4 KB Created: 2021-01-11 11:55:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 283611909862ed33a34a41e19b789bbb SHA-1: 745617f81f820b82a6254c8f20826ebe7e645521 SHA-256: 7c70c862e7fc698cb14e43f5103d91a7448703bbdc7b72a02e966af04a92b3cc
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical alert for a PDF link farm containing numerous external URLs. The ML classifier also assigned a high probability of maliciousness. The primary attack pattern appears to be the distribution of a large number of links to other PDF documents, potentially for SEO spam or to host further malicious content. No scripts were extracted, but the presence of many external links suggests a downloader or redirector functionality.

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-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://traffine.ru/aws?utm_term=bluebook+citation+format+for+law+review+articles
    • https://cdn.sqhk.co/waxigapo/Qhaji7A/jofasigugor.pdf
    • https://cdn.sqhk.co/birenejar/fcmjfij/sadodotexixowax.pdf
    • https://cdn-cms.f-static.net/uploads/4387046/normal_5f93b05b8bab6.pdf
    • https://static.s123-cdn-static.com/uploads/4481061/normal_5ff5a85490ad6.pdf
    • https://cdn.sqhk.co/vovewotutal/4aCjnts/mawuxex.pdf
    • https://bemazinava.weebly.com/uploads/1/3/4/8/134890863/merozupudij-fojegobedepaxe.pdf
    • https://cdn.sqhk.co/vizoxaxijojo/gificja/arizona_shooting_range.pdf
    • https://vibitidit.weebly.com/uploads/1/3/4/7/134712982/laranejarepolo-xakapademuvalo.pdf
    • https://static.s123-cdn-static.com/uploads/4469836/normal_5ffae8ddd694d.pdf
    • https://cdn-cms.f-static.net/uploads/4482853/normal_5fc317dbf158f.pdf
    • https://static.s123-cdn-static.com/uploads/4415964/normal_5ff496a76478a.pdf
    • https://cdn.sqhk.co/jivaduzar/iaEghij/fidget_spinner_3d_model.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/lijulijowivaze/integrated_math_answer_key.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_off0000dab6.bin
9578513a64e8250db3fecbce1c839e8da6106cf7d3ed6b304d8cefc0ba5172d6
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB6 5432 bytes
font_01_sfnt_off0000ed3e.bin
778243d32ed34e8a1c6a39fdbfa0b7a9dd40b94b88387e70ee06ee90283b3f4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xED3E 10408 bytes