CVE-2026-1678

CRITICAL EPSS 29.4%

Published Mar 5, 20263mo ago · Modified Jun 17, 20261w ago

9.8 CVSS 3.1

Critical

Published Mar 5, 2026 3mo ago

Last Modified Jun 17, 2026 1w ago

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.

CVSS Details

Base Score

9.8

Exploitability

3.9

Impact

5.9

Vector string

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

User Interaction None

Scope Unchanged

Confidentiality High

Integrity High

Availability High

Threat Intelligence

EPSS Exploit Probability

29.4% percentile

Exploit & Patch Status

Public Exploit Known

Patch Available

Weaknesses 1

CWE-787 Out-of-bounds Write Memory Safety

Affected Products 1

Vendor	Product	Version	Range
zephyrproject	zephyr	*	≤4.3.0

References 1

github.com https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42

ExploitPatchVendor Advisory

Remediation

github.com https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-536f-h63g-hj42

ExploitPatchVendor Advisory