Malicious PDF — malware analysis report

Static analysis result for SHA-256 3478be7eeae5fab5…

MALICIOUS

PDF

93.8 KB Created: 2021-03-05 23:14:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: cbce5b664cfc94d4010eeeda2a2d6c70 SHA-1: 76b25e9889d04fea93ad96f6598ba083d46fffaf SHA-256: 3478be7eeae5fab5d16927bdaf3bf2a3f3c89c9387db7c66d4c4e93fa0d22a88
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with a critical heuristic firing indicating a link to known malicious redirector infrastructure at 'https://yafferge.ru/strik?utm_term=relative+pronoun+test+with+answers'. Another heuristic identified the PDF as a link farm on disposable hosting, with a sample URL being 'http://linza.media/bategegar5c7vb.pdf'. The ML classifier and ClamAV also flagged this PDF as malicious, suggesting a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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=relative+pronoun+test+with+answers In PDF document text
    • http://linza.media/bategegar5c7vb.pdfIn PDF document text
    • http://sevezor.scienceontheweb.net/unitypoint_urgent_care_altoona_hours.pdfIn PDF document text
    • http://bonifacy.site/kapexetokuxdcei.pdfIn PDF document text
    • http://xumupizaxuto.scienceontheweb.net/zojalusojivonujon.pdfIn PDF document text
    • http://espacecmb.xyz/civil_war_april_1865srlv8.pdfIn PDF document text
    • http://wubosilafusim.iblogger.org/kindle_ebook_format_extension.pdfIn PDF document text
    • http://nakrutkavk.site/caveat_petition_format_madras_high_courtuwan6.pdfIn PDF document text
    • http://hackins.site/depera6o164.pdfIn PDF document text
    • http://nogowipijuw.22web.org/vawakabogezarigutuxibiwe.pdfIn PDF document text
    • http://gululujenij.22web.org/android_emulator_for_windows_7_light.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/zalisujezajaje/ar_15_parts_manual.pdfIn PDF document text
    • http://muvekalufisu.atwebpages.com/20096232291.pdfIn PDF document text
    • http://vizawenep.epizy.com/nicomachean_ethics_book_7_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db3def00-5cbe-4948-928b-70e5517bd3cf/samsung_bd_j5700_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/236b1785-e2c8-4d61-a9ac-80843a626fea/how_to_write_an_introduction_about_yourself_for_a_blog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd727bb9-d164-4861-96cb-c241e71e3d3e/cuanto_vale_el_metro_lineal_de_granito.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f574bef-06b1-47dd-a3b3-f2f92fc7dc1b/where_is_tintern_abbey_located.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f332ee4-1ece-4a05-bf1d-1d9b28d1053d/6575410547.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ca2fa26d-c67b-412c-9485-49831c116fc1/85406605357.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6e987ce-3ef2-4809-a15b-6445fc74c21c/divugovonuloganoweputiwuv.pdfIn PDF document text
    • https://s3.amazonaws.com/safenalavojuwu/lamibixagikono.pdfIn PDF document text
    • https://s3.amazonaws.com/nufidibodudulad/love_status_video_mp4.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010b99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B99 4948 bytes
SHA-256: 1c1266f7f3f4f72c01f563be4ebaf7388b2cc79d8cb02fcbca1c9b7eb240dccb
font_01_sfnt_off00011c75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C75 12380 bytes
SHA-256: f11f2e825815db5fd841191723bf4d8e779434609712f77a3c1086820cdb1cca
font_02_sfnt_off0001440f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1440F 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e
font_03_sfnt_off0001593f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1593F 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34