Malicious PDF — malware analysis report

Static analysis result for SHA-256 672cbb8ac105f5c0…

MALICIOUS

PDF

69.1 KB Created: 2021-03-25 13:42:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b646fa3521aba345c5f4ee8ec8684b4e SHA-1: 2227f71c7711326655799c1b6fde7549e29cc069 SHA-256: 672cbb8ac105f5c08603664b394240671ff1a94584be627f4af4402cec8ae247
156 Risk Score

Malware Insights

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

The file is a PDF that contains numerous external links, a technique often used for SEO spam or to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URL points to a domain associated with potentially malicious activity, while other links lead to S3 buckets that may host further payloads or be part of a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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/award?keyword=essentials+of+biophysics+p+narayanan+pdf+download
    • http://nomevojererekan.22web.org/breville_juice_fountain_cold_plus_recipes.pdf
    • http://tigafik.mygamesonline.org/41039118482.pdf
    • http://zosigar.iblogger.org/cessna_182q_poh_download.pdf
    • https://mafidusat.weebly.com/uploads/1/3/4/1/134109097/2d1c76dbd949.pdf
    • http://niwopofe.scienceontheweb.net/tunajosirisugu.pdf
    • https://pejexiguwela.weebly.com/uploads/1/3/1/1/131164442/b887a5b3d6be35.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/gewuwasi/32762728394.pdf
    • https://s3.amazonaws.com/zuniverijesud/ahista_ahista_movie_hd_video_song.pdf
    • http://sogisujomixugo.epizy.com/tizugukeforuruwabifovanuk.pdf
    • https://s3.amazonaws.com/legesiliv/iu_plagiarism_test_answers_quizlet.pdf
    • https://s3.amazonaws.com/mesixadelomomo/51306759267.pdf
    • https://s3.amazonaws.com/kavalukato/dolmen_mall_tariq_road_store_guide.pdf
    • https://s3.amazonaws.com/sasufufa/78330873354.pdf
    • https://s3.amazonaws.com/vibasujefir/vector_addition_by_components_worksheet_answers_the_physics_classroom.pdf
    • https://s3.amazonaws.com/fadupazageraf/timovokajuxekerojidijoker.pdf
    • https://s3.amazonaws.com/libeganot/pedoni.pdf
    • https://s3.amazonaws.com/miwolezedubujoz/national_incident_reporting_system_nhs.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d06d.bin
7125eba71ac4eedb86c64b7b0ea269dd42a9d2eaa0512fb7e048cc1ccdd9bb74
pdf-font-stream PDF embedded font (sfnt) at offset 0xD06D 5536 bytes
font_01_sfnt_off0000e34a.bin
162457f60f4b220e048817c4ef2a6a976b7e467b7df6cf5d9f8b6fa6f67667cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xE34A 10484 bytes