CVE-2025-27497 OpenDJ Denial of Service (Dos) using alias loop
An attacker can cause the OpenDJ LDAP server to become unresponsive by triggering an alias loop during a search request.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-27497?
CVE-2025-27497 is a high-severity denial of service vulnerability in OpenIdentityPlatform OpenDJ, published on 5 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OpenDJ is an LDAPv3 compliant directory service. OpenDJ prior to 4.9.3 contains a denial-of-service (DoS) vulnerability that causes the server to become unresponsive to all LDAP requests without crashing or restarting. This issue occurs when an alias loop exists in the LDAP database. If an ldapsearch request is executed with alias dereferencing set to "always" on this alias entry, the server stops responding to all future requests. Fortunately, the server can be restarted without data corruption. This vulnerability is fixed in 4.9.3.
Weakness: CWE-835
Which versions are affected by CVE-2025-27497?
2 open source packages ship an affected version, including org.openidentityplatform.opendj:opendj-server-legacy.
| Package | Affected | Fixed in |
|---|---|---|
org.openidentityplatform.opendj:opendj-server-legacy Maven | All versions | 4.9.3 |
org.openidentityplatform.opendj:opendj-server-legacy Maven | All versions | 4.9.3 |
How do I fix CVE-2025-27497?
Upgrade org.openidentityplatform.opendj:opendj-server-legacy to 4.9.3 or later.
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-2025-27497 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-27497 exists.
Sources
Also known as GHSA-93qr-h8pr-4593.