Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc634202259fd1b3…

MALICIOUS

PDF

108.3 KB Created: 2021-04-08 18:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5ad537f1bbff2fbd6f2c2eba43f91ee1 SHA-1: cc53ba9010dc9c4eba9809c8d44bd8d1d67b2bff SHA-256: cc634202259fd1b3b0b3b1e31ed458d22ced050366e5bd71fbc0157fa3b3319c
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs, with a primary suspicious URL being https://nipisod.ru/strik. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is designed to host many links on disposable hosting, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the overall structure and heuristics point to a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://nipisod.ru/strik?utm_term=feelings+and+emotions+faces+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4485153/normal_5fd67ec7b73c0.pdfIn PDF document text
    • http://buzifun.22web.org/45658818346.pdfIn PDF document text
    • https://julamukipupa.weebly.com/uploads/1/3/0/7/130739907/dijutijexe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421637/normal_5fd960194308e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392869/normal_5fec023b784ec.pdfIn PDF document text
    • https://kufifelukabi.weebly.com/uploads/1/3/5/2/135297374/fawamolajuporaf.pdfIn PDF document text
    • http://fepotarugagi.22web.org/62922447407.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409997/normal_6035e36a1be0d.pdfIn PDF document text
    • https://lugilalosu.weebly.com/uploads/1/3/4/3/134314137/nupuli_fedopamik_dejaxaf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gipomafusabakix.rf.gd/murevokeverunimivifu.pdfIn PDF document text
    • http://nixonijokafov.rf.gd/nomenclatura_quimica_inorganica_ejercicios_resueltos.pdfIn PDF document text
    • http://kujazidi.epizy.com/cisco_nexus_9000_vrf_configuration_guide.pdfIn PDF document text
    • http://bokatevifelu.epizy.com/abnormal_psychology_ronald_comer.pdfIn PDF document text
    • http://xafekejo.epizy.com/66385291777.pdfIn PDF document text
    • https://60f6da8c-824c-4163-aae9-6195f2ac7ed4.filesusr.com/ugd/7f16bd_624a6549f91a4905bec00670af3caa36.pdf?index=trueIn PDF document text
    • http://makijozexu.rf.gd/denon_avr_1312_4k.pdfIn PDF document text
    • https://s3.amazonaws.com/lixasifasi/6942771067.pdfIn PDF document text
    • https://s3.amazonaws.com/tazibabebamep/coreldraw_16_portable_free.pdfIn PDF document text
    • https://fac30f9c-1bc3-4ff6-ac40-7ced1d2a170b.filesusr.com/ugd/3b7182_d17dbb7809194e50947b262c1628fff8.pdf?index=trueIn PDF document text
    • https://24d1f61b-f5c5-4d2f-8180-62589f44e8d8.filesusr.com/ugd/eed56f_2b7542bb49404f11be7ebc72ee45b19d.pdf?index=trueIn PDF document text
    • http://difesasud.epizy.com/field_trip_report_for_kindergarten.pdfIn PDF document text
    • https://fa07519e-5664-4b29-af9c-2c502e53c954.filesusr.com/ugd/cbe325_37247cef227c41ce84be5d23638480b2.pdf?index=trueIn PDF document text
    • https://71e5fc8e-cc9a-4633-96c3-2c70acd464d0.filesusr.com/ugd/f08e01_7169736203f44666a632e2eaa9477997.pdf?index=trueIn PDF document text
    • http://jepafuzezax.epizy.com/88941822391.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_off00016775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16775 5332 bytes
SHA-256: f9b105e7e831601d43b4a7f6de68c1f2ab0c6be617ab9d2ccc7f27e6a3aae143
font_01_sfnt_off00017993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17993 11976 bytes
SHA-256: 365567c22db57c895d86d72adbdacc2b806c95f17ac4e422cf7c5a68f9dc2059