{"id":"CVE-2026-5066","title":"net: sockets: tls: Potential out-of-bounds write/read in socket_op_vtable::connect function","summary":"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() memc…","severity":"medium","cvss":6.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","cvssSource":"cna","cwe":["CWE-787"],"vendor":"zephyrproject-rtos","product":"Zephyr","affected":["Zephyr < 3.7.2","Zephyr >= 4.0.0 < 4.2.2","Zephyr >= 4.3.0 < 4.3.1"],"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-06-05T18:26:28.322491Z"},"exploitAvailable":true,"published":"2026-06-04","updated":"2026-10-15","sourceUpdated":"2026-10-15T22:10:24.916Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-5066","references":[{"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-wgrc-jrf6-24f3"}],"tags":["cve.org","exploit-available"],"epss":0.00467,"epssPercentile":0.38869,"ingestedAt":"2026-10-15T22:48:25.574Z","slug":"CVE-2026-5066","body":"## Overview\n\nA 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.\n\n## Affected\n\n- `Zephyr < 3.7.2`\n- `Zephyr >= 4.0.0 < 4.2.2`\n- `Zephyr >= 4.3.0 < 4.3.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":47,"depthScoreParts":{"impact":34.7,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[]}