CVE-2026-5066

A potential out-of-bounds write/read exists in the TLS socket connect path of the network sockets subsystem (subsys/net/lib/sockets/sockets_tls.c). When the TLS session cache is enabled, tls_session_store() and tls_session_restore() memcpy the caller-supplied address into a fixed-size buffer using the caller-controlled addrlen value without validating it against the destination size. struct net_sockaddr is an opaque type, so an application can pass an addrlen larger than sizeof(struct net_sockaddr) (for example 128 bytes into a 24-byte stack buffer), causing the memcpy to read and write past the end of the address memory used by the TLS session cache. This out-of-bounds write can lead to a crash and denial of service, and potentially to arbitrary code execution.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-wgrc-jrf6-24f3	Exploit Patch Vendor Advisory
https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-wgrc-jrf6-24f3	Exploit Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-04 21:16

Updated : 2026-07-22 20:10

NVD link : CVE-2026-5066

Mitre link : CVE-2026-5066

CVE.ORG link : CVE-2026-5066

JSON object : View

Products Affected

zephyrproject

zephyr

CWE

CWE-787

Out-of-bounds Write

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