Malicious PDF — malware analysis report

Static analysis result for SHA-256 d98ddb87248b3235…

MALICIOUS

PDF

81.1 KB Created: 2021-04-22 10:57:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: d25ddd0ff0bce7dd9bbb2dc7fae6f028 SHA-1: b0680a2622b989b32971a60adc5d797d394d83a3 SHA-256: d98ddb87248b3235408801022e74a58f1e23c9eae914ca5528e0a7a9f4704f1e
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are part of a link farm, indicating a likely phishing or malware distribution scheme. The presence of external URIs and the link farm heuristic strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://zajinet.ru/strik?utm_term=bram+stoker+dracula+1992+netflix PDF link annotation
    • http://rejorevubirobu.sportsontheweb.net/dell_e6410_i7_laptop_price.pdfIn PDF document text
    • https://cdn.sqhk.co/zafupusapun/WiijdCy/free_printable_coordinate_graphing_pictures_worksheets.pdfIn PDF document text
    • https://cdn.sqhk.co/rawewosit/K4hfXic/turn_off_roaming_mode_android.pdfIn PDF document text
    • http://biniwitovo.mywebcommunity.org/surah_al_waqiah_in_english.pdfIn PDF document text
    • https://cdn.sqhk.co/jijatidos/iJr0ljc/5112486273.pdfIn PDF document text
    • https://dezijetide.weebly.com/uploads/1/3/4/8/134864221/4899499.pdfIn PDF document text
    • http://gifavojam.scienceontheweb.net/500_basic_chinese_characters.pdfIn PDF document text
    • https://cdn.sqhk.co/libuzewis/e6gji87/rifudopa.pdfIn PDF document text
    • https://cdn.sqhk.co/gufemazibafi/wibVGja/zewebazi.pdfIn PDF document text
    • https://zanugikujo.weebly.com/uploads/1/3/4/3/134399251/7922e6a0.pdfIn PDF document text
    • http://gobitujesan.scienceontheweb.net/91403839545.pdfIn PDF document text
    • http://domotoj.sportsontheweb.net/galabobubili.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d3cf521-2553-46ab-b0d0-f5af996fcd04/dupemimusuviwepule.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0c0af2b-547b-4a32-903b-f508b1b1c5fa/gusasuxupebonupipo.pdfIn PDF document text
    • http://medazupu.onlinewebshop.net/stanford_anesthesia_guide.pdfIn PDF document text
    • http://kubomefewofumim.atwebpages.com/89246407051.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc6b7ef9-cab7-4b64-b03c-74fce17c5c9a/8757275496.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97db244f-1332-4282-ba88-bfefb0ba4d97/somozesekuneloka.pdfIn PDF document text
    • http://jenotuxeje.onlinewebshop.net/telanapekifudebuxagigejer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0582eba0-eeb8-4d10-a554-076d02960c71/bible_quiz_on_genesis_chapter_1_and_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd3ec2e7-f5de-4a2b-a36f-3efd87313ce5/how_to_thread_a_sewing_machine_singer_fashion_mate.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB41 5688 bytes
SHA-256: 7109fce5c871310ef17b66f42f60a9a6ca1dd5b69e72d00d564b716455c87505
font_01_sfnt_off00010e90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E90 12556 bytes
SHA-256: 9351051ff2c15fa320aa57c790ceac3931043f7d200a603eea4879ac0a8483b4