This vulnerability occurs when the Linux kernel executes a network driver callback, cpsw_ndo_set_rx_mode, in a context that does not hold the required RTNL lock. The call path involves IPv6 multicast join operations, which trigger the driver without the lock, causing an assertion failure inside vlan_for_each. The primary result is a kernel panic or service disruption rather than direct remote exploitation. The weakness is a race condition or improper locking error.

Vendors: Linux (Linux kernel). Affected versions include kernel releases 6.19.0-rc1 through 6.19.0-rc8 and any downstream distributions that use these kernels. The flaw is present in kernel code handling the cpsw_new network driver, which is part of the common Linux networking stack.

The CVSS base score is 5.5, indicating moderate severity. The EPSS score is below 1%, suggesting a very low but nonzero probability of exploitation. The vulnerability is not listed in the CISA KEV catalog. The likely attack vector is a local user performing IPv6 multicast group joins, such as via setsockopt, which triggers the problematic code path. An attacker with local privileges can induce the kernel to hit the assertion, potentially causing a denial‑of‑service by crashing the networking stack. No remote or elevated‑privilege exploitation is indicated by the available data.