HIGH
rxrpc Response Race
CVE-2026-31676
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
KernelScan AI6.4MEDIUM
01Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: only handle RESPONSE during service challenge Only process RESPONSE packets while the service connection is still in RXRPC_CONN_SERVICE_CHALLENGING. Check that state under state_lock before running response verification and security initialization, then use a local secured flag to decide whether to queue the secured-connection work after the state transition. This keeps duplicate or late RESPONSE packets from re-running the setup path and removes the unlocked post-transition state test.
02KernelScan AI Analysis
Risk summary
Network attackers can trigger a state handling flaw in RxRPC service connection handling by sending duplicate or late RESPONSE packets, causing kernel crashes or denial of service. This affects systems running AF_RXRPC services such as AFS servers.
Vulnerability analysis
The vulnerability is a state management issue in RxRPC service connection handling. The original code processed RESPONSE packets without first verifying that the connection was still in the RXRPC_CONN_SERVICE_CHALLENGING state, allowing duplicate or late RESPONSE packets to re-run security verification and initialization. This can lead to double-initialization of security contexts or state corruption, resulting in a kernel crash or denial of service. The fix adds proper state checking under state_lock before processing RESPONSE packets and uses a local secured flag to safely queue work only after a valid state transition.
03Fix Versions
| Branch | Fixed in | Patch commit |
|---|---|---|
| 6.12 | 6.12.84 | 29b44d904dce |
| 6.18 | 6.18.23 | d0035e634dae |
| 6.19 | 6.19.13 | 03fd2ef73cb4 |
| 6.6 | 6.6.136 | a6bcf8010af0 |
| mainline | 7.0 | c43ffdcfdbb5 |