CVE-2026-10678
Zephyr MCTP-over-I2C+GPIO bug allows memory corruption via malicious I2C master.
Is CVE-2026-10678 being exploited?
Not confirmed. CVE-2026-10678 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.39% probability of exploitation in the next 30 days.
How severe is CVE-2026-10678?
CVE-2026-10678 is rated High with a CVSS score of 8.1. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-10678?
Yes. A fix has been recorded for CVE-2026-10678. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-10678 affect?
CVE-2026-10678 affects Zephyr RTOS subsys/pmci/mctp/mctp_i2c_gpio_target.c, Zephyr v4.3.0, Zephyr v4.4.0, Devices using Zephyr MCTP-over-I2C+GPIO target binding. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-10678?
Upgrade Zephyr to the fixed release or apply vendor patch; restrict/untrust I2C masters.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
A malicious or malfunctioning I2C bus master can trigger NULL deref or one-byte heap overflow, causing memory corruption, hard fault, or potential code execution/DoS.
Patch when possible
- affected>= 4.3.0 and < 4.5.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.