Out-of-bounds write in Linux kernel - CVE-2026-98456
Published: October 22, 2026
Vulnerability details
The vulnerability allows a local user to corrupt kernel memory, potentially causing a denial of service.
The vulnerability exists due to a race condition leading to an out-of-bounds write in the Bluetooth management function read_unconf_index_list() when controller flags change between counting eligible controllers and filling the response. A local user can request the unconfigured controller index list during asynchronous controller setup to trigger a write beyond the allocated response buffer, potentially crashing the kernel.
Affected software
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
How to mitigate CVE-2026-98456
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
External References
- https://git.kernel.org/stable/c/2e8bba0360d1379bfa8da47c8f5dadbb10a3fba1
- https://git.kernel.org/stable/c/416546cd6a54e9b68f2b91bc680b1ee17dcd77a1
- https://git.kernel.org/stable/c/524e0450dd9a396f99a81b045219b0e2ea0dab57
- https://git.kernel.org/stable/c/8ddf962c76432a10a6cb80042875cbc48a9c056b
- https://git.kernel.org/stable/c/b5dbb41b212c50c095a4dbee3017a84fe94f033b