xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()

{
  "id": "c207293e99e6c55f7dc452dcd3716285e2fc00635a1403deacd8dfbcd8cbcb35",
  "url": "https://osv.dev/vulnerability/CVE-2026-31406",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini()",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: xfrm: Fix work re-schedule after cancel in xfrm_nat_keepalive_net_fini() After cancel_delayed_work_sync() is called from xfrm_nat_keepalive_net_fini(), xfrm_state_fini() flushes remaining states via __xfrm_state_delete(), which calls xfrm_nat_keepalive_state_updated() to re-schedule nat_keepalive_work. The following is a simple race scenario: cpu0 cpu1 cleanup_net() [Round 1] ops_undo_list() xfrm_net_exit() xfrm_nat_keepalive_net_fini() cancel_delayed_work_sync(nat_keepalive_work); xfrm_state_fini() xfrm_state_flush() xfrm_state_delete(x) __xfrm_state_delete(x) xfrm_nat_keepalive_state_updated(x) schedule_delayed_work(nat_keepalive_work); rcu_barrier(); net_complete_free(); net_passive_dec(net); llist_add(&net->defer_free_list, &defer_free_list); cleanup_net() [Round 2] rcu_barrier(); net_complete_free() kmem_cache_free(net_cachep, net); nat_keepalive_work() // on freed net To prevent this, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync().",
    "evidence": "osv:CVE-2026-31406",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.12.80",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.21",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.19.11",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-31406",
      "aliases": [
        "CVE-2026-31406"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "f531d13bdfe3f4f084aaa8acae2cb0f02295f5ae"
                },
                {
                  "fixed": "32d0f44c2f14d60fe8e920e69a28c11051543ec1"
                },
                {
                  "fixed": "2255ed6adbc3100d2c4a83abd9d0396d04b87792"
                },
                {
                  "fixed": "21f2fc49ca6faa393c31da33b8a4e6c41fc84c13"
                },
                {
                  "fixed": "daf8e3b253aa760ff9e96c7768a464bc1d6b3c90"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31406.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.11.0"
                },
                {
                  "fixed": "6.12.80"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.21"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "6.19.11"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31406.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:28.117291735Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/21f2fc49ca6faa393c31da33b8a4e6c41fc84c13",
        "https://git.kernel.org/stable/c/2255ed6adbc3100d2c4a83abd9d0396d04b87792",
        "https://git.kernel.org/stable/c/32d0f44c2f14d60fe8e920e69a28c11051543ec1",
        "https://git.kernel.org/stable/c/daf8e3b253aa760ff9e96c7768a464bc1d6b3c90",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31406.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-31406",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31406.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-31406",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 494555,
  "published_at": "2026-04-06T07:38:18.84+00:00"
}