Malicious PDF — malware analysis report

Static analysis result for SHA-256 99fa4227aada4990…

MALICIOUS

PDF

78.4 KB Created: 2021-04-01 22:55:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a18b839ddf545e4d18ab62fa93d83426 SHA-1: 3841a1882e7d6def260e388ddea71f0f95255993 SHA-256: 99fa4227aada49906a148315940c085a82d1b85903d15d3f3bbf6b88fe0d0444
96 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URL pointing to 'nipisod.ru', which is likely part of the phishing lure. The document body, though heavily obfuscated, appears to contain references to the URL's keyword, suggesting a content-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • 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/wix?keyword=inside+out+riley%2527s+little+brother
    • http://pokanupat.iblogger.org/free_sheet_music_il_silenzio_trumpet.pdf
    • https://cdn-cms.f-static.net/uploads/4428331/normal_604daeac3a1cc.pdf
    • https://cdn-cms.f-static.net/uploads/4458389/normal_60278998edd9e.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/busutafitufe/what_is_comptia_server.pdf
    • https://uploads.strikinglycdn.com/files/fbad3f2e-6cbb-4721-9061-0d8eac8a83da/jubona.pdf
    • https://s3.amazonaws.com/widuxade/doodle_god_alchemy_guide.pdf
    • http://zaxalamel.rf.gd/59833267648.pdf
    • https://s3.amazonaws.com/temujonuwu/blanket_order_agreement_template.pdf
    • http://mesodixole.rf.gd/76822203896.pdf
    • https://uploads.strikinglycdn.com/files/338b0536-fe16-4845-808b-b92e746f77e9/is_how_to_train_your_dragon_real.pdf
    • http://wubezirinipo.epizy.com/51540435077.pdf
    • https://uploads.strikinglycdn.com/files/8a2dd2cb-7147-4819-8822-5d09a6519931/pomites.pdf
    • https://uploads.strikinglycdn.com/files/aeb4ef69-967d-45b0-b657-9c152c99ec49/fikulobuda.pdf
    • https://s3.amazonaws.com/desekusoxi/bernina_1230_bobbin_tension.pdf
    • https://uploads.strikinglycdn.com/files/2bb7c55e-0cb1-41f3-be48-cb72058fc160/lord_of_the_rings_books_author.pdf
    • https://s3.amazonaws.com/gofilafixu/gatosunaxir.pdf
    • https://s3.amazonaws.com/poresi/film_basara_3_sub_indo.pdf
    • http://ketaxesam.epizy.com/bt_broadband_setup_guide.pdf
    • https://s3.amazonaws.com/dudigonifu/dr_babasaheb_ambedkar_hd_wallpaper.pdf
    • https://uploads.strikinglycdn.com/files/e50f8a09-11a6-4ed2-b0d3-6ee53ba5b693/67295104861.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_off0000f6d6.bin
6241af4841611f4960f8d13bc34e59f93dac1527ec460b3b1efbb2393c632431
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D6 4916 bytes
font_01_sfnt_off0001078c.bin
4562bc8d28dec419afd06f0a1dba4f30aaf0eb2cfff353191ccf38f32935a3a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x1078C 10908 bytes