Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b2c87a544d6971d…

MALICIOUS

PDF

76.1 KB Created: 2021-04-06 07:19:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 8d5de8f1b90e146a667fb1be1b5bac45 SHA-1: 5afc1b21c8dc5bed4888cdd5f04dac1fb96d4bc9 SHA-256: 1b2c87a544d6971d21f550050cf41d5acb0dcfecd1325ec1c62f6c9ab32cbb0e
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://jumiwimov.ru/123?utm_term=sight+word+practice+worksheets+1st+grade PDF link annotation
    • https://pozetegafikule.weebly.com/uploads/1/3/4/8/134857311/1597528.pdfIn PDF document text
    • http://regivag.iblogger.org/share_agreement_contract.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454995/normal_5fec4d5cb23ce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489599/normal_6063199fe8b56.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420599/normal_600fcd4179aa0.pdfIn PDF document text
    • https://tojumemi.weebly.com/uploads/1/3/1/3/131379390/1505401.pdfIn PDF document text
    • https://sovawetozinunur.weebly.com/uploads/1/3/1/4/131407226/sutubewenadi.pdfIn PDF document text
    • https://mitesevutij.weebly.com/uploads/1/3/4/7/134717039/bodolusige-dujesegijo.pdfIn PDF document text
    • http://jojowezumuxup.22web.org/37218261413.pdfIn PDF document text
    • http://bimiwefumukiv.22web.org/bootstrap_4_checkout_form_code.pdfIn PDF document text
    • https://nogexumojadug.weebly.com/uploads/1/3/4/2/134235638/7b32f1.pdfIn PDF document text
    • https://kafubururi.weebly.com/uploads/1/3/4/2/134235359/edd819d3c6.pdfIn PDF document text
    • https://bimekofag.weebly.com/uploads/1/3/4/5/134596958/3172169.pdfIn PDF document text
    • https://wedezetepeb.weebly.com/uploads/1/3/4/5/134528952/3824313.pdfIn PDF document text
    • https://lemorixumo.weebly.com/uploads/1/3/4/7/134748879/zupubivima_kuwibirisog.pdfIn PDF document text
    • http://gubevexezu.iblogger.org/circuit_analysis_theory_and_practice_5th_edition_answers.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/fefdcdec-3193-4864-8ace-e812f6c472fb/51434508643.pdfIn PDF document text
    • http://fakaxuman.epizy.com/65012987279.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d1913c0-1158-47e3-a478-62ffaff0ef0f/will_there_be_another_stock_market_crash_in_2020.pdfIn PDF document text
    • http://xazogugikuriwox.rf.gd/wuwinulojetejirivegaso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/662dd090-4e91-4a19-b71c-1454f0e71a04/latin_root_word_mitosis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dfe3ed4b-346e-4378-8e94-fbe549ac886b/quran_english.pdfIn PDF document text
    • http://likuxusodim.epizy.com/43116855470.pdfIn PDF document text
    • http://jokilezitewoj.epizy.com/english_grammar_book_for_class_9.pdfIn PDF document text
    • http://nokonasaxe.epizy.com/rugiwugikazagoxov.pdfIn PDF document text
    • http://votarim.epizy.com/bewawifojumarozixetisevit.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_off0000ebd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBD1 5612 bytes
SHA-256: df728ef7a461eff4bfc08e666d127b44c148675850e32fea484ad98fde519774
font_01_sfnt_off0000feff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFF 10284 bytes
SHA-256: 4d65ac21ba4465bff98ddfc71fe6d0b7e67665f2133267bf33da06cd853aac7b