CVE-2026-103552 Denial of service in Apache Directory LDAP API
An attacker can cause a stack overflow and denial of service by sending a deeply nested search filter to the server using the vulnerable library.
- 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-2026-103552?
CVE-2026-103552 is a high-severity denial of service vulnerability in Apache Directory LDAP API, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Stack Overflow vulnerability in Apache Directory LDAP API.
Before binding, a client can send a deeply nested search filter that overflows the stack in the server's decoder.
This issue affects Apache Directory LDAP API: from 1.2.0 before 1.2.9.
Users are recommended to upgrade to version 1.2.9, which fixes the issue.
Weakness: CWE-121
Which versions are affected by CVE-2026-103552?
How do I fix CVE-2026-103552?
No fix has been published for CVE-2026-103552 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-2026-103552 being exploited?
There is no known exploitation of CVE-2026-103552 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-103552, GHSA-mggr-349m-j697, UBUNTU-CVE-2026-103552.