CVE-2026-10634
June 15, 2026, 8:52 p.m.
4.8
Medium
Description
Zephyr's native TCP stack iterates the global connection list in net_tcp_foreach() (subsys/net/ip/tcp.c) using the SYS_SLIST_FOR_EACH_CONTAINER_SAFE macro, which caches a pointer to the next list node. Prior to this fix the function released tcp_lock while invoking the per-connection callback and re-acquired it afterwards. During that window a concurrent tcp_conn_release(), running on the dedicated TCP work-queue thread when a connection's reference count drops to zero (e.g. a remote peer closing or resetting the connection), can remove and k_mem_slab_free() the cached next connection. When the iterator advances it dereferences the freed (and possibly reallocated) slab memory — a use-after-free that can crash the system (denial of service) and, if the slot has been reused, cause the callback to operate on an attacker-influenced object (potential information disclosure or further fault). net_tcp_foreach() is reached in production via the 'net conn' network shell command and via net_tcp_close_all_for_iface() on interface-down; the freeing side is driven by ordinary TCP traffic. The fix moves the connection/context teardown in tcp_conn_release() inside the tcp_lock critical section and keeps tcp_lock held across the callback in net_tcp_foreach(). The defect was introduced with the modern (TCP2) stack in 2020 and affects releases up to and including v4.4.0.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Zephyrproject |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-416
Use After Free
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| a | zephyrproject | zephyr | / | / | / | / | / | / | / | / |
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: ADJACENT_NETWORK
- Attack Complexity: HIGH
- Privileges Required: LOW
- Scope: UNCHANGED
- Confidentiality Impact: NONE
- Integrity Impact: NONE
- Availability Impact: HIGH
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Timeline
Published: June 15, 2026, 4:16 p.m.
Last Modified: June 15, 2026, 8:52 p.m.
Last Modified: June 15, 2026, 8:52 p.m.
Status : Awaiting Analysis
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.