CVE-2026-53521 — MEDIUM (6.4)

Vulnerability Description

Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 2.0.14 to before version 2.1.0, PATCH /server/{id} accepts and persists nonexistent ddns_profiles IDs for a member-owned server. If another user later creates a DDNS profile with one of those IDs, the DDNS worker resolves the stored ID and dispatches an update using the other user's DDNS profile configuration in the context of the attacker's server. This issue has been patched in version 2.1.0.

CVSS Score

6.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

CHANGED

Confidentiality

NONE

Integrity

LOW

Availability

LOW

Related Weaknesses (CWE)

CWE-863

References

FAQ

What is CVE-2026-53521?

CVE-2026-53521 is a vulnerability with a CVSS score of 6.4 (MEDIUM). Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 2.0.14 to before version 2.1.0, PATCH /server/{id} accepts and persists nonexistent ddns_pr...

How severe is CVE-2026-53521?

CVE-2026-53521 has been rated MEDIUM with a CVSS base score of 6.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-53521?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.