Use-after-free in Linux kernel - CVE-2026-72393
Published: August 15, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in fbnic_tx_lso in the fbnic transmit offload path when processing a specially crafted GSO skb that triggers skb reallocation. A local user can send crafted traffic to trigger the stale shared-info pointer dereference to cause a denial of service.
The issue occurs because skb_cow_head() may reallocate the skb and its shared info before the cached pointer is reused.
Affected software
Ubuntu
linux (Ubuntu package)
linux-realtime (Ubuntu package)
linux-oracle (Ubuntu package)
linux-gcp (Ubuntu package)
linux-aws (Ubuntu package)
linux-raspi (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-ibm (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-gke (Ubuntu package)
linux-aws-7.0 (Ubuntu package)
linux-nvidia-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-azure (Ubuntu package)
How to mitigate CVE-2026-72393
linux (Ubuntu package) - update to 7.0.0-34.34
linux-realtime (Ubuntu package) - update to 7.0.0-34.34.1
linux-oracle (Ubuntu package) - update to 7.0.0-1012.12
linux-gcp (Ubuntu package) - update to 7.0.0-1013.13
linux-aws (Ubuntu package) - update to 7.0.0-1013.13
linux-raspi (Ubuntu package) - update to 7.0.0-1020.20
linux-nvidia (Ubuntu package) - update to 7.0.0-1025.26
linux-ibm (Ubuntu package) - update to 7.0.0-1014.14
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2022.23
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-34.34~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1013.13~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1012.12~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1014.14
linux-gke (Ubuntu package) - update to 7.0.0-1007.8
linux-aws-7.0 (Ubuntu package) - update to 7.0.0-1013.13~24.04.1
linux-nvidia-7.0 (Ubuntu package) - update to 7.0.0-1024.25~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1017.17
External References
Related Security Bulletins
- Use-after-free in Linux kernel meta fbnic driver
- Ubuntu update for linux-gcp
- Ubuntu update for linux
- Ubuntu update for linux-oracle-7.0
- Ubuntu update for linux-gke
- Ubuntu update for linux-azure-7.0
- Ubuntu update for linux-azure
- Ubuntu update for linux-nvidia-7.0, linux-nvidia-bos
- Ubuntu update for linux-nvidia