A local user or process that can connect to the sssd‑kcm UNIX socket may trigger a denial of service by sending an oversized request length header and then stalling the connection. The component preallocates a large amount of memory in response, consuming system resources until the process is killed or the system becomes unresponsive. This flaw, identified as CWE‑770, results in memory exhaustion of the sssd‑kcm responder and fulfills a classic denial‑of‑service condition.

The vulnerability affects all Red Hat Enterprise Linux releases 6 through 10 and the Red Hat OpenShift Container Platform 4 that bundle the sssd‑kcm component. Because the flaw is triggered via a local UNIX socket, any system where local users have write access to that socket is at risk, regardless of the specific minor version within those major releases.

The attack can only be performed by a local attacker with the ability to reach the sssd‑kcm socket, so remote exploitation is not possible. Nonetheless, the lack of a published workaround or patch means that any privileged local user could exhaust memory and cause a DoS. The EPSS score is < 1% and the CVSS score is 5.5, indicating moderate severity; the vulnerability is not listed in CISA’s KEV catalog, but given the simplicity of the exploit and the moderate impact, the risk remains significant for environments where local access is broad.