Stack-based buffer overflow in Linux kernel - CVE-2026-31772

Vulnerability identifier: #VU128922

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-31772

CWE-ID: CWE-121

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to stack-based buffer overflow in hci_le_big_create_sync when processing a crafted ISO socket configuration. A local user can bind an ISO socket with a large number of BIS entries and call listen() to cause a denial of service.

The issue is triggered when the number of BIS entries is between 18 and 31, leading to a stack out-of-bounds write in the HCI command sync worker.

Linux kernel
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Ubuntu
kernel (Red Hat package)
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - addressed in versions 5.14.0-687.17.1.el9_8, 6.12.0-211.26.1.el10_2
linux (Ubuntu package) - addressed in versions 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-aws (Ubuntu package) - update to 6.8.0-1061.64+1
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-azure-fips (Ubuntu package) - update to 6.8.0-1063.71+fips2
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1

• https://git.kernel.org/stable/c/aba0aea354015794e8312dd7efe726967e58aefe
• https://git.kernel.org/stable/c/bc39a094730ce062fa034a529c93147c096cb488
• https://git.kernel.org/stable/c/eaf32002ca7b1ba51c9f140991fd9febe6de79f0
• https://git.kernel.org/stable/c/f5d446624345d309e7a4a1b27ea9f028d6a8c5d9

• Stack-based buffer overflow in Linux kernel bluetooth
• Red Hat Enterprise Linux 10 update for kernel
• Red Hat Enterprise Linux 9 update for kernel
• Ubuntu update for linux
• Ubuntu update for linux-gcp-fips
• Ubuntu update for linux-oracle-6.8
• Ubuntu update for linux-fips
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-azure-fde-6.8
• Ubuntu update for linux-azure-fips
• Ubuntu update for linux-azure-fde
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Ubuntu update for linux-hwe-6.8
• Ubuntu update for linux-aws-6.8
• Ubuntu update for linux-ibm