{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "3.6.0"
                  },
                  {
                    "fixed": "4.3.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              },
              {
                "range": [
                  {
                    "introduced": "4.4.0"
                  },
                  {
                    "fixed": "4.4.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              },
              {
                "range": [
                  {
                    "fixed": "cd85e0e890ab89815c4cbc0a8fbc03a3efa84dc2"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              }
            ]
          },
          "events": [
            {
              "introduced": "468eb56cf242eedba62006ee758700ee6148763f"
            },
            {
              "fixed": "75f67d766726351b30199f9a2bf55803d717a3be"
            },
            {
              "introduced": "684c9e8f32e4373a21098559f748f06915f950c9"
            },
            {
              "fixed": "1f6485eca25431b5ff27ce9a754218c9e559bbbb"
            },
            {
              "fixed": "cd85e0e890ab89815c4cbc0a8fbc03a3efa84dc2"
            }
          ],
          "repo": "https://github.com/zephyrproject-rtos/zephyr",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-6c57-xfhw-j26x"
  ],
  "database_specific": {
    "cna_assigner": "zephyr",
    "cwe_ids": [
      "CWE-416"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10634.json"
  },
  "details": "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.\n\nDuring 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).\n\nnet_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.\n\nThe 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.",
  "id": "CVE-2026-10634",
  "modified": "2026-10-28T02:30:50.610253349Z",
  "published": "2026-06-15T14:16:43.871Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10634.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-6c57-xfhw-j26x"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-10634"
    },
    {
      "type": "FIX",
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/cd85e0e890ab89815c4cbc0a8fbc03a3efa84dc2"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/zephyrproject-rtos/zephyr"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Use-after-free in Zephyr native TCP `net_tcp_foreach()` due to dropping `tcp_lock` during the callback"
}