CVE-2026-31638
Published: April 25, 2026Last modified: May 1, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Only put the call ref if one was acquired rxrpc_input_packet_on_conn() can process a to-client packet after the current client call on the channel has already been torn down. In that case chan->call is NULL, rxrpc_try_get_call() returns NULL and there is no reference to drop. The client-side implicit-end error path does not account for that and unconditionally calls rxrpc_put_call(). This turns a protocol error path into a kernel crash instead of rejecting the packet. Only drop the call reference if one was actually acquired. Keep the existing protocol error handling unchanged.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Not affected (6.1.33-r0) |
| 25 LTS | linux-lts | Fixed (6.12.85-r0) | |
| Stream | linux-lts | Fixed (6.12.85-r0) |
References
- https://git.kernel.org/stable/c/0c156aff8a2d4fa0d61db7837641975cf0e5452d
- https://git.kernel.org/stable/c/6331f1b24a3e85465f6454e003a3e6c22005a5c5
- https://git.kernel.org/stable/c/8299ca146489664e3c0c90a3b8900d8335b1ede4
- https://git.kernel.org/stable/c/9fb09861e2b8d1abfe2efaf260c9f1d30080ea38
- https://git.kernel.org/stable/c/b8f66447448d6c305a51413a67ec8ed26aa7d1dd