CVE-2026-1678 (GCVE-0-2026-1678)
Vulnerability from cvelistv5 – Published: 2026-03-05 06:21 – Updated: 2026-03-05 15:28
VLAI?
Title
dns: memory‑safety issue in the DNS name parser
Summary
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.
Severity ?
9.4 (Critical)
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| zephyrproject-rtos | Zephyr |
Affected:
* , ≤ 4.3
(git)
|
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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