A heap out-of-bounds write vulnerability was found in the Linux kernel's RPC-over-RDMA server reply path in net/sunrpc/xprtrdma/svc_rdma_sendto.c. When a crafted RPC-over-RDMA client sends a large NFS READ request with an empty Write list and no Reply chunk, the server linearizes the entire multi-page reply into a fixed-size 4096-byte heap buffer without bounds checking, resulting in a kernel heap overflow. This can lead to denial of service via kernel crash or potential code execution through corruption of adjacent kernel heap objects.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1