CVE-2023-53873 SyncBreeze 15.2.24 Denial of Service via Login Endpoint Overflow
Attackers can crash the SyncBreeze service by sending oversized password parameters to the login endpoint, disrupting availability.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2023-53873?
CVE-2023-53873 is a high-severity denial of service vulnerability in SyncBreeze, published on 15 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
SyncBreeze 15.2.24 contains a denial of service vulnerability in the login authentication mechanism that allows attackers to crash the service. Attackers can send an oversized password parameter with repeated 'password=' values to overwhelm the login endpoint and potentially disrupt service availability.
Weakness: CWE-400
Which versions are affected by CVE-2023-53873?
How do I fix CVE-2023-53873?
No fix has been published for CVE-2023-53873 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-53873 being exploited?
There is no known exploitation of CVE-2023-53873 in the wild and no public exploit code.
Sources
Also known as GHSA-h7mp-qf49-hgph.