Heap-based buffer overflow in Linux kernel - CVE-2026-64502

Vulnerability identifier: #VU139428

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-2026-64502

CWE-ID: CWE-122

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to corrupt the heap and cause a denial of service.

The vulnerability exists due to a heap-based buffer overflow in ad_sigma_delta_clear_pending_event() when handling pending events with num_resetclks set to 0. A local user can trigger the pending-event drain path to corrupt the heap and cause a denial of service.

The issue can occur for registerless devices without an RDY GPIO and also for devices with an RDY GPIO set when the pending event condition is detected.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-azure (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1011.11, 7.0.0-1014.14
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1

• https://git.kernel.org/stable/c/3394e0b3328422431cadaf314fa58d3717ed4936
• https://git.kernel.org/stable/c/3bceb26dfaf7ba805b459e41c1d0ba916862dade
• https://git.kernel.org/stable/c/91bc6767a4f55dc470d8a56b55b9f2ea09094efe

• Heap-based buffer overflow in Linux kernel iio adc driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0
• Ubuntu update for linux-oracle-7.0
• Ubuntu update for linux-azure
• Ubuntu update for linux-azure-7.0