Medium severity · published Jun 12, 2026
CVE-2026-53521
Nezha Monitoring: Stored future DDNS profile ID allows unauthorized use of another user's DDNS profile context
6.4
CVSS
0.3%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
nezha · nezhahq
>= 2.0.14, < 2.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53521
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-53521
github.com
https://github.com/nezhahq/nezha/security/advisories/GHSA-39g2-8x68-pmx8
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