Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec087d8bd8712543…

MALICIOUS

PDF

67.9 KB Created: 2021-03-10 22:44:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dc616f89134993e86519c91d8a608ed0 SHA-1: e1d1482e7141c7c59fd516258da67f052e0c486f SHA-256: ec087d8bd8712543843987e30f84f7d40b5a367dfaf569a39bf81cfe6b2ad314
126 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV and an ML classifier as malicious, specifically as a phishing trojan. It contains numerous external URIs, with one pointing to zajinet.ru, which is likely part of a link farm designed to redirect users to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://zajinet.ru/wix?keyword=mardel+bookstore+tulsa+oklahoma
    • http://vafakewa.iblogger.org/pudozixiwon.pdf
    • http://fikosarodone.medianewsonline.com/38396661650.pdf
    • http://edapog.online/32121648996e9oq6.pdf
    • http://gamukanemafutu.mywebcommunity.org/2010_camaro_zl1_convertible_for_sale.pdf
    • http://rusadezebep.mygamesonline.org/override_replace_toner_brother_mfc_7860dw.pdf
    • http://xibawolafubiz.getenjoyment.net/93980776079.pdf
    • http://how2clever.com/rukowazixah3dly.pdf
    • http://rigoditibalun.mywebcommunity.org/delonghi_pinguino_portable_air_conditioner.pdf
    • http://kepuxom.mypressonline.com/mefofisebup.pdf
    • http://kigurumi.org/things_i_used_to_do_in_my_childhoodou7k8.pdf
    • http://meetlait.pro/samsung_hw-j550_wall_mountqbc4m.pdf
    • http://nogurufegu.mygamesonline.org/gvd-504a_battery_replacement.pdf
    • http://fulilip.iblogger.org/conversation_analysis_report_example.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://e055bcc9-c4f1-4c6c-8dcb-0912bf54750f.filesusr.com/ugd/b4a829_45451bc3acd64602be4c0e63b76d0f5b.pdf?index=true
    • https://s3.amazonaws.com/julaxel/ginurebikalonobefepevovow.pdf
    • http://sukoxaji.rf.gd/confederacy_of_dunces_movie_curse.pdf
    • https://s3.amazonaws.com/fifuto/77346524463.pdf
    • https://s3.amazonaws.com/desekusoxi/premikudu_audio_songs_ing_telugu_lo.pdf
    • https://f3dbd103-cf2f-44fc-b0ad-c9004dc38af2.filesusr.com/ugd/1f2646_07f6c1c18a9d4f9c9b98c8fd5762904c.pdf?index=true
    • http://fafamofuwinofen.epizy.com/78887835046.pdf
    • https://217ba8a6-026c-4a9e-b1ce-2eadff0a4a08.filesusr.com/ugd/3d7af5_f81c53ab579b4e7c87614e3bd1c26d8e.pdf?index=true
    • http://kepagewav.atwebpages.com/rawagukifovexajiduv.pdf
    • https://s3.amazonaws.com/xomudufe/class_10_physical_science_book.pdf
    • https://ed21222e-fee3-4fab-8b52-e2ddb7bb35ab.filesusr.com/ugd/e73fea_ccd341eda2004da4bb4260e83f35bf66.pdf?index=true
    • https://cee4a208-09ac-40e0-983f-4c2cc776acbe.filesusr.com/ugd/5ed537_ea4f7ab1478e48e5af39d1d9e654d8f1.pdf?index=true
    • https://s3.amazonaws.com/nasitevu/how_to_answer_do_i_know_you_questions.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_off0000cdf8.bin
a026eacedb7219cdfc96f54581954cd59722037f14589a9b735041f7e69da6ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDF8 5272 bytes
font_01_sfnt_off0000dfc1.bin
00df9aaa0217a816be8d0fa61d491eaa6aa7a35808f7138b938a4339874b0bb3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC1 10044 bytes