Malicious PDF — malware analysis report

Static analysis result for SHA-256 52b8d04cff637652…

MALICIOUS

PDF

77.4 KB Created: 2021-04-08 02:53:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 22ecdbd047e4e1d0acd8b5ad963fb1ef SHA-1: b1465ac9788933ab06e730a32c023edc7da2a779 SHA-256: 52b8d04cff637652ae8740ba7ff29d5e6d26a000dc2b67a8e581f47531a03b88
184 Risk Score

Malware Insights

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

The PDF contains embedded links pointing to known malicious redirector infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The ML classifier also strongly flagged this PDF as malicious. The primary malicious IOC is the URL 'https://yafferge.ru/wix?keyword=future+problem+solving+categories', which is likely used to redirect users to a phishing or malware-hosting site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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/wix?keyword=future+problem+solving+categories In PDF document text
    • https://kumeboxisadinur.weebly.com/uploads/1/3/4/6/134684257/lufezuxob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415292/normal_601bcf673827b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371788/normal_5ff39c23a7ea3.pdfIn PDF document text
    • http://nipuxikupiluzep.iblogger.org/mathematics_syllabus_d_book_3.pdfIn PDF document text
    • https://nudadisaxoge.weebly.com/uploads/1/3/4/0/134018155/ae2ed4f3e2954.pdfIn PDF document text
    • https://baxufolodamiz.weebly.com/uploads/1/3/1/4/131408032/84007981f.pdfIn PDF document text
    • http://lijamerogavex.iblogger.org/kiran_s_psychological_aptitude_test_book_free.pdfIn PDF document text
    • https://zidadosivifaju.weebly.com/uploads/1/3/0/7/130775619/90a03f8.pdfIn PDF document text
    • http://wanebiwadu.iblogger.org/links_awakening_seashells_interactive_map.pdfIn PDF document text
    • https://zinobelusetepi.weebly.com/uploads/1/3/5/3/135318062/9316828.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450634/normal_605f76854acb1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4530937/normal_60646589a169d.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/04841f19-14f6-4091-bcaf-b5b76a9809b3/rogekamomupafegaduzatu.pdfIn PDF document text
    • https://s3.amazonaws.com/rabewiruzitewa/bexifitatonotorajez.pdfIn PDF document text
    • http://ximogubofew.epizy.com/wagilitolobatofuliranuwi.pdfIn PDF document text
    • http://votizabi.epizy.com/norton_anthology_of_african_american_literature.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8090f449-c237-4feb-a300-21c1ddb64c6d/sharp_el-2196bl_calculator_instructions.pdfIn PDF document text
    • https://s3.amazonaws.com/mozirolinitaje/baiju_bawra_film.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c610a8c3-e004-4c85-9818-ec041dd951ab/texojo.pdfIn PDF document text
    • http://zisajevejeniw.epizy.com/naxof.pdfIn PDF document text
    • http://ralokavuxubu.epizy.com/6260985439.pdfIn PDF document text
    • http://vopepogam.rf.gd/asiana_airline_crash_news_report.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_off0000ef79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF79 5408 bytes
SHA-256: 53538d7cda365f103c5455b2cdd316d6e182b684b7c33ac4db43a635edffda43
font_01_sfnt_off000101d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D1 11036 bytes
SHA-256: 47ed48c6f0c4765c4122bc7b4d4db819aecac846a14dd8a7076bfa9b6f224907