Malicious PDF — malware analysis report

Static analysis result for SHA-256 f58f991bee1dcf6f…

MALICIOUS

PDF

78.9 KB Created: 2021-03-21 03:23:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0884d518dbdf288ebdace396c7ea1bdb SHA-1: e6a1d9b6389fcc81b158fa450e8eeb38da6f3bfb SHA-256: f58f991bee1dcf6ff6ffd8f62175d3ba280c9dfed08d76f3866b2e18b4d3a75d
96 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection, indicating malicious intent. An embedded URI points to 'kuzutuzo.ru', which is likely a phishing or malware distribution domain. The document body, though heavily obfuscated, suggests a lure related to 'firmware vs software'. No scripts were extracted, but the PDF structure itself facilitated the malicious URI.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://kuzutuzo.ru/award?keyword=firmware+vs+software+pdf
    • https://cdn-cms.f-static.net/uploads/4476150/normal_6031d3ce440a4.pdf
    • https://cdn-cms.f-static.net/uploads/4491439/normal_603c1ba3eb82b.pdf
    • https://cdn-cms.f-static.net/uploads/4382618/normal_602d27fd1d3c8.pdf
    • http://kovemiwixipogaf.66ghz.com/vizinen.pdf
    • https://cdn.sqhk.co/wemonamo/eHid7jf/general_motors_customer_service_hours.pdf
    • https://static.s123-cdn-static.com/uploads/4448535/normal_5ff4291a6999f.pdf
    • https://cdn-cms.f-static.net/uploads/4428061/normal_603eacd699e78.pdf
    • https://cdn.sqhk.co/pajokiman/ejeiggd/42872818590.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://xulalozuvemuve.rf.gd/14719918870.pdf
    • http://muvuferoditewum.epizy.com/empirical_distribution_example.pdf
    • https://s3.amazonaws.com/sulasatevirexo/sofegarovarez.pdf
    • https://s3.amazonaws.com/muwomapotumugi/bejukadekenekeno.pdf
    • https://s3.amazonaws.com/satulibaren/valunapewudipusamav.pdf
    • http://desuvusemexemob.epizy.com/raxojageruwigidurusoko.pdf
    • http://fitizoluwa.epizy.com/lagu_yang_terdalam_lyrics.pdf
    • http://nefigubisi.epizy.com/28462707109.pdf
    • http://zesinule.rf.gd/adjustment_entries_in_final_accounts.pdf
    • http://darumanu.rf.gd/panasonic_toughbook_fz-g1_accessories.pdf
    • https://s3.amazonaws.com/wovitiku/soya_bean_production_guidelines.pdf
    • http://zudosikewemer.epizy.com/how_much_does_an_amazon_station_operations_manager_make.pdf
    • http://kavotipuwevir.epizy.com/midodoritowiw.pdf
    • http://xesepodine.rf.gd/perforated_stainless_steel_sheet_philippines.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_off0000f7a9.bin
b6186123dea2fb836f919f4f6ff608c2d2d551bf7061718ff654364e5c88f80e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A9 5260 bytes
font_01_sfnt_off0001098f.bin
12e146148d0ea18793ddd7662fd75c9a04b8f2a47ba59ad8a9c80617ab35c5eb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1098F 10760 bytes