CVE-2026-74666
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ri…
Published Aug 22, 2026 · updated Oct 14, 2026
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ring state under sk_receive_queue.lock, but used to publish the tpacket receive mode through po->prot_hook.func after releasing that lock. packet_poll() and packet_recvmsg() can then run the pressure clearing path after the ring has been cleared while still seeing tpacket_rcv, causing __packet_rcv_has_room() to dereference stale or NULL ring storage. Move the existing receive hook assignment into the same sk_receive_queue.lock section as the ring state update. Keep the assignment otherwise unchanged, including on TX ring reconfiguration, to avoid adding behavior changes that are not required for the fix. Serialize packet_recvmsg() pressure clearing with the same queue lock only after PACKET_SOCK_PRESSURE has been observed. If the flag is clear and the socket has moved away from tpacket_rcv, packet_set_ring() has already detached the socket and waited for synchronize_net(), so no new packet input can set the flag again. packet_poll() already holds sk_receive_queue.lock, so it uses the new unlocked helper directly.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Aug 22, 2026 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ring state under sk_receive_queue.lock, but used to publish the tpacket receive mode through po->prot_hook.func after releasing that lock. packet_poll() and packet_recvmsg() can then run the pressure clearing path after the ring has be
Oct 14, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ring state under sk_receive_queue.lock, but used to publish the tpacket receive mode through po->prot_hook.func after releasing that lock. packet_poll() and packet_recvmsg() can then run the pressure clearing path after the ring has be
Sources
- CVE.orgVulnerability recordCVE-2026-74666
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-74666
30-day exploitation probability 0.1%
first.org - NIST NVDVulnerability recordCVE-2026-74666
In the Linux kernel, the following vulnerability has been resolved: packet: synchronize pressure clearing with ring reconfiguration packet_set_ring() updates the RX ring state under sk_receive_queue.lock, but used to publish the tpacket receive mode through po->prot_hook.func a
nvd.nist.gov