CVE-2026-31638
Published: April 24, 2026· Updated: Apr 27, 2026
Official 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.
Technical Analysis
CVE-2026-31638 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (5)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-31638 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts