Malicious PDF — malware analysis report

Static analysis result for SHA-256 37de804c47642d23…

MALICIOUS

PDF

78.6 KB Created: 2021-03-18 09:25:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: fbdc061eb757f67623a42c9b0b45d6d4 SHA-1: c0a306b1ccfd5b7a965e19b3a1ebd2c4efb55f0e SHA-256: 37de804c47642d2394fdfe553b2e6615d1dfef3714b8ef0660e7a325b9da2bcd
184 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by multiple heuristics and a machine learning classifier, indicating it is likely a phishing or redirection attempt. The embedded links, such as 'https://yafferge.ru/strik?utm_term=youtube+japanese+song+hana+wa+saku+lyrics', point to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://yafferge.ru/strik?utm_term=youtube+japanese+song+hana+wa+saku+lyrics In PDF document text
    • https://cdn.sqhk.co/bigulikexupa/jzBZs82/dubeponobidevorakev.pdfIn PDF document text
    • https://cdn.sqhk.co/fusojafiza/jdLewhb/free_music_to_use_for_instagram_videos.pdfIn PDF document text
    • https://cdn.sqhk.co/sofetarunox/WUgiehi/archipelago_examples_geography.pdfIn PDF document text
    • http://nonly.xyz/bang_bang_tamil_mp4_movie_free2tnaz.pdfIn PDF document text
    • https://cdn.sqhk.co/jadepibake/yhUXHha/withings_scale_bmi_accuracy.pdfIn PDF document text
    • http://igbusinessabouthelp.com/bajepoxefurp45xk.pdfIn PDF document text
    • https://cdn.sqhk.co/beratinuga/gfiiig8/wobes.pdfIn PDF document text
    • http://idealslimitalia-ufficiale.site/63613305327byw3h.pdfIn PDF document text
    • http://hookup755.fun/prayer_god_simulator_apkjd2ib.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://rozopujonabesix.epizy.com/rovedisisok.pdfIn PDF document text
    • http://wesofidufu.rf.gd/dpe_assistant_teacher_exam_result_2020_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8d8d8543-1629-4097-830a-28ca60861e8d/bar_course_fees_uk.pdfIn PDF document text
    • http://faripemisale.rf.gd/8th_class_english_grammar_book_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d3592f43-09ef-405a-8c9c-34a638c34efc/angles_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8b5f4e7-cf19-4edd-929c-ac0a202697ce/31580441441.pdfIn PDF document text
    • http://siwegop.rf.gd/2620316586.pdfIn PDF document text
    • http://demurib.rf.gd/cbse_biology_project_on_cancer.pdfIn PDF document text
    • http://wesamejoz.epizy.com/preeclampsia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/749d76ed-8d93-45a6-8549-94de041fb31f/the_boy_who_harnessed_the_wind_online_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/edcc9be5-9262-477a-af8a-a42d00d43ec9/xasadobuk.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e49a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE49A 5628 bytes
SHA-256: 0b7951a41c9e60f4db158e268cde1c144ac97e71361d06525447c29a7a7f3c22
font_01_sfnt_off0000f7ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7CE 6068 bytes
SHA-256: cb159cc9d714520fdf604515834a8e5d6ccdf81551317d8133b939af7313f940
font_02_sfnt_off0001077e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1077E 10952 bytes
SHA-256: 888dfd188db0f3f6770637802265237513123e765c4e070c55088d2afffc24b3