Malicious PDF — malware analysis report

Static analysis result for SHA-256 965c4e2c55926c2f…

MALICIOUS

PDF

80.6 KB Created: 2021-03-25 05:56:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 4ef625f4293dd6650244145232c82847 SHA-1: c92e1e704d848dd00815743a9e8c0a369d4b85a1 SHA-256: 965c4e2c55926c2fcd943bbb493129f185db645ae1bc87a6057d6adb8d4f5e60
126 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous embedded URLs pointing to external PDF files hosted on disposable domains, suggesting a link farm or redirection mechanism. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a likely attempt to drive traffic to malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://baarspo.ru/award?keyword=biblia+de+estudio+reina+valera+1960+para+descargar+gratis+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4474218/normal_5ff2e2c1b383e.pdfIn PDF document text
    • http://wosedumuf.mywebcommunity.org/anatomy_of_upper_limb_muscles.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4486983/normal_600779b111c82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476936/normal_604b9eb4b7268.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466411/normal_5fe6eae2c366d.pdfIn PDF document text
    • http://xojuxelase.medianewsonline.com/betegodu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410194/normal_600d486a6e177.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405907/normal_605396ec575ee.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369935/normal_5fccfc08ec03d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445106/normal_6056363450911.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454558/normal_6058ea4fd6c31.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369905/normal_60445ada41c77.pdfIn PDF document text
    • http://nebuxopav.mypressonline.com/40469511437.pdfIn PDF document text
    • http://gapilojazixo.getenjoyment.net/how_to_put_my_essay_in_mla_format.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484633/normal_600390f7d185e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470689/normal_6023d14d5cc93.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488806/normal_5fdb1839c1e61.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4505687/normal_5ff65b01ea494.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485172/normal_6004cb271de4f.pdfIn PDF document text
    • http://tejidirexe.mywebcommunity.org/advanced_excel_training_courses_uk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479902/normal_602e1bc846406.pdfIn PDF document text
    • http://fotubobuwenapu.scienceontheweb.net/excel_macros_online_tutorial.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369633/normal_6037d5fd4da40.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475853/normal_5fe86b31895d5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zimopup.myartsonline.com/cathy_o_brien_book_tranceformation_of_america.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE412 6076 bytes
SHA-256: ebd0e12f4f1e21e5938e540bcf6593a2012c5158887bd8c07582205972a3a128
font_01_sfnt_off0000f8d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D3 10972 bytes
SHA-256: ce95badef636bb4a6381d15384f62ca64e18397edda40ee0847105ac9355ee4c
font_02_sfnt_off00011d0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D0D 16092 bytes
SHA-256: 9af6fc3bf9d751f70540aea0fa47faa159a3604992cda23d2adcda3ffc5346b2