CVE-2021-47588

A flaw was found in the Linux kernel's Simple Internet Transition (SIT) tunneling driver. When an error occurs during network initialization, the driver attempts to release network device resources that have already been freed. A local attacker can exploit this condition to trigger a kernel crash, resulting in a Denial of Service (DoS).

This vulnerability is rated as a Low severity issue for Red Hat Enterprise Linux because exploitation requires local access and relies on an uncommon failure condition during network namespace initialization. The Simple Internet Transition (SIT) tunneling module is not active by default unless explicitly configured or loaded for IPv6-over-IPv4 tunneling. Furthermore, the issue only manifests on device registration error paths, limiting the blast radius to a denial of service without compromising system confidentiality or integrity.

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.