A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function in the LDAP server does not enforce an upper bound on the number of controls per LDAP message. A remote, unauthenticated attacker can send a specially crafted LDAP request containing hundreds of thousands of minimal controls within the default maximum BER message size (2 MB), causing excessive CPU consumption and heap allocation on the server. Under concurrent exploitation, this leads to significant latency degradation, worker thread starvation, or out-of-memory termination, resulting in a denial of service.
https://access.redhat.com/errata/RHSA-2026:27125
https://access.redhat.com/errata/RHSA-2026:26639
https://access.redhat.com/errata/RHSA-2026:26599
https://access.redhat.com/errata/RHSA-2026:26597
https://access.redhat.com/errata/RHSA-2026:26465
https://access.redhat.com/errata/RHSA-2026:26464
https://access.redhat.com/errata/RHSA-2026:26463
https://access.redhat.com/errata/RHSA-2026:26461
https://access.redhat.com/errata/RHSA-2026:26460
https://access.redhat.com/errata/RHSA-2026:26459
https://access.redhat.com/errata/RHSA-2026:26458
https://access.redhat.com/errata/RHSA-2026:26457
https://access.redhat.com/errata/RHSA-2026:26456
https://access.redhat.com/errata/RHSA-2026:26455
https://access.redhat.com/errata/RHSA-2026:26454