CVE-2026-89466 power: supply: qcom_battmgr: terminate the strings from firmware
A missing null terminator in the Qualcomm battery manager driver allows reading adjacent kernel memory when firmware sends full-length strings.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89466?
CVE-2026-89466 is a high-severity vulnerability in Linux, published on 11 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
power: supply: qcom_battmgr: terminate the strings from firmware
The qcom_battmgr_sc8280xp_strcpy() takes a Pascal-style string when the firmware sends one. Otherwise it copies all BATTMGR_STRING_LEN bytes and leaves the destination without a terminator.
Those destinations are model_number, serial_number and oem_info, each BATTMGR_STRING_LEN and declared next to each other. They go out to user space as val->strval, which power_supply_format_property() prints with "%s", so a firmware string that fills the whole field makes that read run into the following members.
Use strscpy() so the copy always terminates, the way the SM8350 path already does for the same field.
Which versions are affected by CVE-2026-89466?
How do I fix CVE-2026-89466?
Apply the vendor's patch.
Is CVE-2026-89466 being exploited?
There is no known exploitation of CVE-2026-89466 in the wild and no public exploit code.
Sources
Also known as AZL-100782, BELL-CVE-2026-89466, DEBIAN-CVE-2026-89466, GHSA-g9cw-qg44-9g2q, UBUNTU-CVE-2026-89466.