CVE-2026-12804 lemonldap-ng SAML Common Domain Cookie Endpoint CDC.pm redirect
Remote attackers can exploit an open redirect in the SAML Common Domain Cookie Endpoint, though impact is low as the feature is rarely used.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-12804?
CVE-2026-12804 is a medium-severity vulnerability in lemonldap-ng, published on 21 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A vulnerability was detected in lemonldap-ng up to 2.23.0. Impacted is an unknown function in the library lemonldap-ng-portal/lib/Lemonldap/NG/Portal/CDC.pm of the component SAML Common Domain Cookie Endpoint. Performing a manipulation of the argument url results in open redirect. The attack is possible to be carried out remotely. The exploit is now public and may be used. Applying a patch is the recommended action to fix this issue. The vendor confirms, that "it has been fixed some days ago and will be available in 2.23.1. CDC is quite never used, so the impact is very low."
Weakness: CWE-601
Which versions are affected by CVE-2026-12804?
How do I fix CVE-2026-12804?
Apply the vendor's patch.
Is CVE-2026-12804 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12804 exists.
Sources
Also known as DEBIAN-CVE-2026-12804, GHSA-g4v8-q2mr-m933, UBUNTU-CVE-2026-12804.