CVE-2026-1678
criticaldns_unpack_name() caches the buffer tailroom once and reuses it while appending DNS labels.
Vendor / product: Zephyrproject — zephyr
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.
CVSS
9.8
9.8 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-03-05 07:16
Modified: 2026-10-15 23:17
NVD status: Analyzed
Last synced 3 days ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
zephyrproject / zephyr ≤4.3.0
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Vendor advisory: https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42
Vendor advisory: https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42
References
- https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42 vulnerabilities@zephyrproject.org
- https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42 134c704f-9b21-4f2e-91b3-4a467353bcc0
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗