CVE-2026-74429 rxrpc: Fix the reception of a reply packet before data transmission
A null pointer dereference in the Linux kernel's rxrpc module can cause a system crash when a reply packet is received before data transmission.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74429?
CVE-2026-74429 is a high-severity vulnerability in Linux, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix the reception of a reply packet before data transmission
Fix rxrpc_receiving_reply() to handle the reception of an apparent reply DATA packet before rxrpc has had a chance to send any request DATA packets on a client call by checking to see if the call has been exposed yet by sending the first packet.
Without this, rxrpc_rotate_tx_window() might oops.
Also fix rxrpc_rotate_tx_window() to handle the Tx queue being empty by changing the do...while loop into a while loop, just in case a call is abnormally terminated by an early reply before the last request packet is transmitted.
Which versions are affected by CVE-2026-74429?
How do I fix CVE-2026-74429?
Apply the vendor's patch.
Is CVE-2026-74429 being exploited?
There is no known exploitation of CVE-2026-74429 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74429, DEBIAN-CVE-2026-74429, GHSA-p3f2-6553-5mwv, UBUNTU-CVE-2026-74429.