CVE-2026-1678: dns: memory‑safety issue in the DNS name parser
dnsunpackname() 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 CONFIGDNSRESOLVER is enabled.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-1678?
CVE-2026-1678 has a high severity rating due to its potential to allow denial of service attacks through buffer overflows.
How do I fix CVE-2026-1678?
To fix CVE-2026-1678, update to a patched version of the Zephyr project that addresses this memory-safety issue.
Which versions of Zephyr are affected by CVE-2026-1678?
CVE-2026-1678 affects all versions of Zephyr up to and including version 4.3.0.
What type of issue does CVE-2026-1678 represent?
CVE-2026-1678 represents a memory-safety issue caused by improper handling of buffer sizes in the DNS name parser.
What can happen if CVE-2026-1678 is exploited?
If exploited, CVE-2026-1678 can cause buffer overflows leading to potential application crashes or unpredictable behavior.