CVE-2026-53521 json
Nezha Monitoring: Stored future DDNS profile ID allows unauthorized use of another user's DDNS profile context
published 4mo ago modified 17d ago also GHSA-39g2-8x68-pmx8 , GO-2026-5826 , EUVD-2026-36600
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- go github.com/nezhahq/nezha 2.1.0
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
Is CVE-2026-53521 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.27% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/nezhahq/nezha/security/advisories/GHSA-39g2-8x68-pmx8 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L |
| GitHub | 3.1 | 6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/nezhahq/nezha | >=2.0.14, <2.1.0 all versions |
2.1.0 |
Affected products
- nezhahq nezha
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/nezhahq/nezha/security/advisories/GHSA-39g2-8x68-pmx8
exploit, web, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-53521
advisory
-
github.com
/nezhahq/nezha
package
Sources
- CVE List CVE-2026-53521
- GitHub Advisory GHSA-39g2-8x68-pmx8
- NVD CVE-2026-53521
- OSV GO-2026-5826
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