Critical CVSS 9.1
CVE-2026-52539
Outstatic CMS <= 2.1.9 contains a hardcoded JWT signing secret. When the OST_TOKEN_SECRET environment variable is not set, the application falls back to the default value which is publicly visible in the source code repository. An unauthenticated remote attacker can exploit this by forging JWT session tokens with arbitrary user data and full administrative permissions.
What this means
- Exposure
- Exploitable remotely over the network, without authentication and with no action from the victim.
- Impact
- An attacker can read sensitive data and modify or destroy data.
- Weakness
- Credentials are hard-coded in the product and identical across every installation.
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doPatch without waiting for the next scheduled cycle. Start with the instances exposed to the internet.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.