Technical impact
A flaw in the SSSD NSS responder allows a local attacker to send a specially crafted GETHOSTBYADDR request that bypasses validation of the addrlen field, resulting in an out‑of‑bounds read. The malformed packet causes the responder process to crash, which leads to a denial of service for applications that rely on name service resolution. This weakness is a classic out‑of‑bounds read vulnerability (CWE‑125).
Affected Systems
The vulnerability affects Red Hat Enterprise Linux 6 through 10 and Red Hat OpenShift Container Platform 4, as issued by Red Hat. All components that run the SSSD NSS responder on these platforms are potentially impacted, regardless of specific minor or patch level, because the CVE description does not specify version constraints.
Risk and Exploitability
The CVSS score of 5.5 indicates moderate severity. EPSS is not available, so current exploitation probability is unknown, and the vulnerability is not listed in the CISA KEV catalog. The attack requires local privilege or local network access to the NSS responder socket, making the risk lower than remote exploits. However, a crash can disrupt name resolution for the impacted host, so the overall risk is Medium to Low without widespread public exploitation.
