CVE-2025-21764

A vulnerability was found in the Linux kernel's IPv6 Neighbor Discovery (NDISC) subsystem, which manages network neighbor information. The issue arises from improper synchronization mechanisms when allocating socket buffers (sk_buff) in the ndisc_alloc_skb() function. Specifically, the function can be called without holding the necessary Read-Copy-Update (RCU) or Routing Netlink (RTNL) locks, leading to a potential use-after-free (UAF) condition. This flaw allows an attacker with local access and low privileges to exploit the race condition, potentially causing system instability or crashes.

Michael Randrianantenaina discovered that the Bluetooth driver in the Linux Kernel contained an improper access control vulnerability. A nearby attacker could use this to connect a rougue device and possibly execute arbitrary code. It was discovered that the CIFS network file system implementation in the Linux kernel did not properly verify the target namespace when handling upcalls. An attacker could use this to expose sensitive information.