CVE intelligence and bounded remediation

CVE-2025-66450 — LibreChat is a ChatGPT clone with additional features

High CVSS 8.6

LibreChat is a ChatGPT clone with additional features. In versions 0.8.0 and below, when a user posts a question, the iconURL parameter of the POST request can be modified by an attacker. The malicious code is then stored in the chat which can then be shared to other users. When sharing chats with a potentially malicious “tracker”, resources loaded can lead to loss of privacy for users who view the chat link that is sent to them. This issue is fixed in version 0.8.1.

Severity
High
CVSS
8.6 (4.0)
Published
2025-12-11
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-80

Affected products

  • librechat / librechat

Matched remediation archetype

Cross-site scripting and unsafe browser output

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace reflected, stored, and DOM-derived untrusted values into HTML, attributes, URLs, styles, scripts, and client-side template sinks.
  • Identify affected origins, authenticated user roles, sensitive browser capabilities, and where content is shared across tenants.
  • Review framework escaping, rich-text sanitization, legacy templates, and client-side rendering paths.

Remediate safely

  • Use context-aware framework output encoding and safe DOM APIs; keep untrusted data out of executable contexts.
  • Sanitize intentionally supported markup with a maintained allowlist policy and validate URLs and attributes separately.
  • Update affected rendering components and add tests for every output context using inert sentinel markup.

Authoritative sources

Complete CVE record and remediation plan

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