CVE-2025-51606

hippo4j 1.0.0 to 1.5.0, uses a hard-coded secret key in its JWT (JSON Web Token) creation. This allows attackers with access to the source code or compiled binary to forge valid access tokens and impersonate any user, including privileged ones such as "admin". The vulnerability poses a critical security risk in systems where authentication and authorization rely on the integrity of JWTs.

CVSS v3.1 CNA

8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

0.35% chance of exploitation in the next 30 days, 28th percentile

Published

2025-08-21

Updated

2025-08-22

Proof-of-concept exploits (1)

• ShenxiuSec/cve-proofs/blob/main/POC-20250610-01.md20★ · 2026-02-17

Security advisories

• advisories/GHSA-48cg-9c55-j2q7

References

• CVE Record
• NVD entry

Related

• CVE-2025-4175
• CVE-2025-4178
• CVE-2025-4328
• CVE-2025-4511
• CVE-2025-4542
• CVE-2025-4838