Malicious PDF — malware analysis report

Static analysis result for SHA-256 8addbf423d51f7f7…

MALICIOUS

PDF

79.4 KB Created: 2021-04-06 05:26:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 038e04fa682006b7ec15aa41553976c6 SHA-1: acba976c5a22cfa6e1e37e703d0a7042b3c26632 SHA-256: 8addbf423d51f7f74f3fd9c5c22299247549009158c0e0ea3e69effecbf5f17f
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are SEO-optimized, suggesting a link farm or phishing attempt. The primary malicious URL identified is https://xezojetit.ru/strik, which is likely used to redirect the user to a malicious site. ClamAV also detected this file as Pdf.Phishing.Trojan.

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://xezojetit.ru/strik?utm_term=what+are+the+age+limits+for+joining+the+military
    • http://legivupipofu.66ghz.com/bhu_bsc_ag_application_form_2019.pdf
    • http://pidebuzuvufugi.22web.org/36471961995.pdf
    • http://fogugevup.22web.org/8th_grade_social_studies_textbook.pdf
    • http://rezefad.22web.org/30348854480.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://1a6c606f-1efd-495f-9370-57f425d809fd.filesusr.com/ugd/1be480_a6cc4c93777a47069fed355ff8f3a5fc.pdf?index=true
    • https://fb1cd387-549b-40f1-a5a4-67fd65d29bb3.filesusr.com/ugd/4200b4_99ce21a8e4ca48dcb6a63aa5a15c1380.pdf?index=true
    • https://9d50af6f-dbf7-41ba-b854-83985329a12b.filesusr.com/ugd/33c377_0e96d4638c964eb9b561c29d28f0bf52.pdf?index=true
    • https://b7af6bb9-01eb-4839-ab56-764651de4344.filesusr.com/ugd/2486b5_19c9c048d7c34966a1629aa458b02c46.pdf?index=true
    • https://s3.amazonaws.com/luborinizu/dusopevujexevorilizu.pdf
    • https://s3.amazonaws.com/kelageketisefuv/75125633774.pdf
    • https://s3.amazonaws.com/panalipolifod/canonical_and_standard_forms_in_dld.pdf
    • https://s3.amazonaws.com/jaxesabi/skyscan_atomic_clocks.pdf
    • http://didaduxazej.epizy.com/daxufigaw.pdf
    • https://s3.amazonaws.com/jupoti/blank_recipe_template.pdf
    • https://s3.amazonaws.com/rumezo/51702464155.pdf
    • https://4b0cdf75-2e42-4830-99f1-bbdbaec3f661.filesusr.com/ugd/891219_cb2329c1462e43ab90c19f2d84601257.pdf?index=true
    • https://s3.amazonaws.com/vuxirefare/what_is_a_feedback_control_model.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_off0000f71c.bin
d4ee256ce983b8d5e9f70b1e1dc6de4432bd568c2d522c201b496adcf6ab7090
pdf-font-stream PDF embedded font (sfnt) at offset 0xF71C 5372 bytes
font_01_sfnt_off00010953.bin
61c27d8011a025871502ca4693df12297aba3ec15126023502cc59224ef1bf7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10953 11356 bytes