SB20261022444 - Use-after-free in Linux kernel rtc driver

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-98826)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to potentially cause a denial of service through access to freed kernel memory.

The vulnerability exists due to use-after-free in the Linux kernel AC100 RTC clock provider when RTC device registration fails after the clock provider has been registered. A local user can potentially trigger a subsequent clock lookup that accesses freed chip->clk_data through of_clk_hw_onecell_get() to cause a kernel fault and denial of service.

The triggering RTC device registration failure occurs only when devm_rtc_register_device() returns -ENOMEM.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/12bcd20d76703ee2baf52224d287b7fea096b12f
• https://git.kernel.org/stable/c/55ca60ba336632349f7c4585d22ba74ae355b7ce
• https://git.kernel.org/stable/c/9cff19ddd7f90c1f572a0f83cfc41de8f8dcbcd8
• https://git.kernel.org/stable/c/fcf0b58e976e83adf246b014518e49c662b96f5e