CVE-2025-21669 Information

Description

In the Linux kernel the following vulnerability has been resolved:

vsock/virtio: discard packets if the transport changes

If the socket has been de-assigned or assigned to another transport we must discard any packets received because they are not expected and would cause issues when we access vsk->transport.

A possible scenario is described by Hyunwoo Kim in the attached link where after a first connect() interrupted by a signal and a second connect() failed we can find vsk->transport at NULL leading to a NULL pointer dereference.

Reference

https://git.kernel.org/stable/c/2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 https://git.kernel.org/stable/c/6486915fa661584d70e8e7e4068c6c075c67dd6d https://git.kernel.org/stable/c/677579b641af109613564460a4e3bdcb16850b61 https://git.kernel.org/stable/c/88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee https://git.kernel.org/stable/c/d88b249e14bd0ee1e46bbe4f456e22e01b8c68de