{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "e1e551bc56302b80ff930c966f9985095fb1b70d"
            },
            {
              "fixed": "b66920a3348c0f63ba18365248fa21fbf0b3a937"
            },
            {
              "fixed": "438b1f668ad58f46ce699bb48e4698a7839e3f9e"
            },
            {
              "fixed": "3733fce2871c9bca9dd18a1a23b1432ea215a094"
            },
            {
              "fixed": "33a3149dd81a1e2f52b80ee1e0fc380b39f3d028"
            },
            {
              "fixed": "069daad4f2ae9c5c108131995529d5f02392c446"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.9.0"
            },
            {
              "fixed": "6.6.136"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.83"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.24"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43091.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Wait for RCU readers during policy netns exit\n\nxfrm_policy_fini() frees the policy_bydst hash tables after flushing the\npolicy work items and deleting all policies, but it does not wait for\nconcurrent RCU readers to leave their read-side critical sections first.\n\nThe policy_bydst tables are published via rcu_assign_pointer() and are\nlooked up through rcu_dereference_check(), so netns teardown must also\nwait for an RCU grace period before freeing the table memory.\n\nFix this by adding synchronize_rcu() before freeing the policy hash tables.",
  "id": "CVE-2026-43091",
  "modified": "2026-07-08T05:37:44.497896827Z",
  "published": "2026-05-06T07:40:23.955Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43091.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43091"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "xfrm: Wait for RCU readers during policy netns exit"
}