CVE-2026-10669: On Xtensa SoCs built with CONFIG_XTENSA_MPU and CONFIG_USERSPACE, arch_buffer_validate() in arch/xtensa/core/m

Q: How do I fix CVE-2026-10669?

zephyr: upgrade to 4.5.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-10669 being exploited?

CVE-2026-10669 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-10669 affect?

CVE-2026-10669 affects zephyr. Severity is high (CVSS 7.8). On Xtensa SoCs built with CONFIG_XTENSA_MPU and CONFIG_USERSPACE, arch_buffer_validate() in arch/xtensa/core/mpu.c — the architecture hook that verifies a user-mode-supplied buffer is accessible to the calling user thread with the requested

Q: How urgent is CVE-2026-10669?

Priority 34/100. High severity; Public exploit reference

Routine

HIGH 7.8UPGRADE

CVE-2026-10669 is a high-severity flaw (CVSS 7.8) affecting zephyr. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

On Xtensa SoCs built with CONFIG_XTENSA_MPU and CONFIG_USERSPACE, arch_buffer_validate() in arch/xtensa/core/mpu.c — the architecture hook that verifies a user-mode-supplied buffer is accessible to the calling user thread with the requested permission — defaulted its return value to 0 (access permitted) and only set a denial result inside its per-MPU-region probe loop. When the rounded extent of the buffer wraps the 32-bit address space (size + a

Why this priority

High severity
Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	7.8 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.2% (top 93%)
CISA exploited list	No
Weakness	CWE-787, CWE-190
Published	2026-07-14
Last modified	2026-10-24

Publisher (CNA): Zephyr Project · Vendor: zephyrproject

Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-07-14 15:16 UTCPublished CVE record published
2026-10-24 21:10 UTCUpdated Record last modified

zephyrproject zephyr UPGRADE

Affected: >= 3.7.0 and < 4.5.0

Fixed in: 4.5.0

Safe to downgrade to: a release before 3.7.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-10669?

zephyr: upgrade to 4.5.0. Exact commands for each OS are on this page.

Is CVE-2026-10669 being exploited?

CVE-2026-10669 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-10669 affect?

CVE-2026-10669 affects zephyr. Severity is high (CVSS 7.8). On Xtensa SoCs built with CONFIG_XTENSA_MPU and CONFIG_USERSPACE, arch_buffer_validate() in arch/xtensa/core/mpu.c — the architecture hook that verifies a user-mode-supplied buffer is accessible to the calling user thread with the requested

How urgent is CVE-2026-10669?

Priority 34/100. High severity; Public exploit reference

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CVE-2026-10667 HIGH 7.8 UPGRADE Zephyr's dynamic kernel-object tracking (kernel/userspace/userspace.c, formerly kernel/userspace.c) maintains
CVE-2026-10664 MEDIUM 5.0 UPGRADE The nRF70 Wi-Fi driver's power-save event handler nrf_wifi_event_proc_get_power_save_info() in drivers/wifi/nr
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References

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