Race condition in Linux kernel - CVE-2026-74726

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a race condition in bond_alb_monitor in the bonding ALB implementation when handling active slave changes under RTNL. A local user can trigger network interface state changes to cause a denial of service.

The issue can lead to a null pointer dereference and kernel panic, and in failover cases can underflow the new slave's promiscuity counter and leave it stuck in promiscuous mode.

Affected software

How to mitigate CVE-2026-74726

External References

• https://git.kernel.org/stable/c/09add8d5cfa9c46828f51eaad162c36e86366b71
• https://git.kernel.org/stable/c/257c4a3a34d8f51efb00f35375a0c6ce3c8f6ce2
• https://git.kernel.org/stable/c/2faf75a8a06504071b4c0aea7e45a9cc49a4e187
• https://git.kernel.org/stable/c/683c6ba6e58e6ed1037831ea97dd58d9c0e76b8d
• https://git.kernel.org/stable/c/b82f51681a7a88c7d3c865e817a3340d42b5fa2a
• https://git.kernel.org/stable/c/dccec0227ed8d9e36936d66e256b957dc2858468
• https://git.kernel.org/stable/c/dd148539fb4741d01c06b7d2c8bd84b01920756c
• https://git.kernel.org/stable/c/f7668762bf5fd6db9397de5c0514407489d9d815

Related Security Bulletins

• Race condition in Linux kernel net bonding driver
• Debian update for linux