CVE-2026-53521: Nezha Monitoring: Stored future DDNS profile ID allows unauthorized use of another user's DDNS profile context
Vulnerability summary
CVE-2026-53521 is a medium (CVSS 6.4) Incorrect Authorization vulnerability in nezhahq nezha. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22.8% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 12-06-2026PublishedVulnerability first disclosed.
- 15-06-2026Last modifiedVulnerability information updated.
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 metrics
3 scores · 3 sources · 1 version- OSV · GoEcosystem advisory · calculated6.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L
- NVDNIST6.4MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L
EPSS trend
Probability
0.31%
Chance of exploitation in the next 30 days
Percentile
23%
Versus all other CVEs
30-day change
Increase +0.08 pp
From 0.23% on 22-09-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Github.com/nezhahq1 product
- nezha≥ 2.0.14, < 2.1.0 | All versions (No fix recorded)
Nezhahq1 product
- nezha≥ 2.0.14, < 2.1.0
2 vendors · 2 products
References
3 links- github.com/nezhahq/nezhaPACKAGE