Zephyr Project warns of a high-severity vulnerability

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[TLP:CLEAR] Zephyr Project warns of a high-severity vulnerability

Zephyr Project warns of a high-severity vulnerability in the Zephyr operating system [1]. At the time of publication of the advisory, no fixed version had yet been released, but the vendor has provided temporary mitigation measures according to the recommendations at [2][3][4][5].

Zephyr Project - DoS, RCE (CVE-2026-1678)

CVSS 9.4 (Critical)

When the DNS resolver functionality is enabled, an unauthenticated remote attacker can trigger an out-of-bounds memory write by sending a specially crafted DNS response, which may lead to a DoS attack or potentially code execution [1].

The vulnerability is present in product:

Zephyr Project; <= 4.3

CVSS: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

More information:

CVE-2026-1678 at cve.org, NVD
CWE-787: Out-of-bounds Write at cwe.mitre.org

The vulnerability was publicly disclosed 5. 3. 2026.

Links

By CESNET, z.s.p.o. Henrieta Paločková on 10. 3. 2026.

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[TLP:CLEAR] Zephyr Project warns of a high-severity vulnerability

Zephyr Project - DoS, RCE (CVE-2026-1678)

CVSS 9.4 (Critical)

Links