CVE-2026-1678
Critical
Description
dns_unpack_name() caches the buffer tailroom once and reuses it while appending DNS labels. As the buffer grows, the cached size becomes incorrect, and the final null terminator can be written past the buffer. With assertions disabled (default), a malicious DNS response can trigger an out-of-bounds write when CONFIG_DNS_RESOLVER is enabled.
SeverityCritical
CVSS9.4
Exploit probability—
ProductZephyr
PublishedMar 5, 2026
First seenMar 5, 2026
Weakness typeCWE-787Out-of-bounds write
How to fix
Update
- zephyrproject zephyr3.7.2, 4.2.2, 4.3.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| zephyrproject zephyr | v ≤ 4.3.0, v < 3.7.2, 4.0.0 ≤ v < 4.2.2, 4.3.0 ≤ v < 4.3.1 | 3.7.2, 4.2.2, 4.3.1 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.