CVE-2026-23479

A flaw was found in Redis. The unblock client flow does not handle an error return from the processCommandAndResetClient when re-executing a blocked command. If a blocked client is evicted during this flow, an authenticated attacker can cause a use-after-free issue. This potentially leads to arbitrary code execution.

To exploit this flaw, a highly specific sequence of events and time dependent conditions that are not directly in control of an attacker must occur, increasing the complexity of exploitation. Additionally, the attacker needs to be authenticated, limiting the exposure of this issue. To reflect these conditions, this vulnerability has been rated with an important severity.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.