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Universal cross-site scripting (UXSS)


Universal cross-site scripting exploits client-side vulnerabilities, either through the browser or the extensions that the user enables, leading to the possibility of cross-side scripting exploitation or the execution of malicious code.


  • Persistently inject malicious JavaScript code. - hijack any session that belongs open in the compromised browser. - Execute malicious code.


Keep your browsers and extensions up to date. Although this is not a definitive solution to the specific vulnerability, always use and install only what is necessary.


Unauthenticated attacker from the Internet with access to the victim's browser.

Expected Remediation Time

⌚ 600 minutes.


Default score using CVSS 3.1. It may change depending on the context of the src.


  • Attack vector: N
  • Attack complexity: H
  • Privileges required: N
  • User interaction: N
  • Scope: C
  • Confidentiality: H
  • Integrity: L
  • Availability: L


  • Exploit code maturity: P
  • Remediation level: U
  • Report confidence: C


  • Vector string: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:L/E:P/RL:U/RC:C
  • Score:
    • Base: 8.1
    • Temporal: 7.7
  • Severity:
    • Base: High
    • Temporal: High

Score 4.0

Default score using CVSS 4.0 . It may change depending on the context of the src.

Base 4.0

  • Attack vector: N
  • Attack complexity: H
  • Attack Requirements: N
  • Privileges required: N
  • User interaction: N
  • Confidentiality (VC): H
  • Integrity (VI): L
  • Availability (VA): L
  • Confidentiality (SC): L
  • Integrity (SI): L
  • Availability (SA): L

Threat 4.0

  • Exploit maturity: P

Result 4.0

  • Vector string: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:L/SI:L/SA:L/E:P
  • Score:
    • CVSS-BT: 7.0
  • Severity:
    • CVSS-BT: High



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