CVE-2026-10677: The CONFIG_USERSPACE syscall verifier z_vrfy_k_poll() in kernel/poll.c allocates a kernel-side copy of the use

Q: How do I fix CVE-2026-10677?

zephyr: upgrade to newer than 4.4.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-10677 being exploited?

CVE-2026-10677 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-2026-10677 affect?

CVE-2026-10677 affects zephyr. Severity is medium (CVSS 6.5). The CONFIG_USERSPACE syscall verifier z_vrfy_k_poll() in kernel/poll.c allocates a kernel-side copy of the user-supplied k_poll_event[] via z_thread_malloc() and then validates each event's object handle. Before this fix, validation used K_

Q: How urgent is CVE-2026-10677?

Priority 24/100. No elevated risk signals yet.

Routine

MEDIUM 6.5UPGRADE

CVE-2026-10677 is a medium-severity flaw (CVSS 6.5) affecting zephyr. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The CONFIG_USERSPACE syscall verifier z_vrfy_k_poll() in kernel/poll.c allocates a kernel-side copy of the user-supplied k_poll_event[] via z_thread_malloc() and then validates each event's object handle. Before this fix, validation used K_OOPS(K_SYSCALL_OBJ(...)) inline inside the loop, which kills the calling thread without freeing events_copy. A user thread can pass num_events >= 1 with a forged object handle to leak the allocation; because n

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.1% (top 97%)
CISA exploited list	No
Weakness	CWE-401
Published	2026-07-21
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

2026-07-21 22:16 UTCPublished CVE record published
2026-10-24 19:10 UTCUpdated Record last modified

zephyrproject zephyr UPGRADE

Affected: >= 1.12.0 and <= 4.4.1

Fixed in: newer than 4.4.1

Safe to downgrade to: a release before 1.12.0

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-2026-10677?

zephyr: upgrade to newer than 4.4.1. Exact commands for each OS are on this page.

Is CVE-2026-10677 being exploited?

CVE-2026-10677 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-2026-10677 affect?

CVE-2026-10677 affects zephyr. Severity is medium (CVSS 6.5). The CONFIG_USERSPACE syscall verifier z_vrfy_k_poll() in kernel/poll.c allocates a kernel-side copy of the user-supplied k_poll_event[] via z_thread_malloc() and then validates each event's object handle. Before this fix, validation used K_

How urgent is CVE-2026-10677?

Priority 24/100. No elevated risk signals yet.

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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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