← Back to CVE Explorer

CVE-2026-99213

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: vsock: treat TCP_CLOSING as once-established Handle the TCP_ESTABLISHED -> TCP_CLOSING transition on OP_RST, which can race with the connect loop. Immediately break and return 0 on ESTABLISHED/CLOSING. The return value of connect() should reflect what happened up to the point the connection was established or failed. Events that occur afterwards must not affect it. E.g. even if OP_RW has already set sk_err, connect() should still return 0, not ENOBUFS because of it. Adapt the inaccurate comment above signal_pending(). Resetting a socket that is still present in connected_table can lead to memory corruption. The reporter noted lost transports for in-flight skbs, and I have reproduced crashes caused by re-insertion into connected_table. list_add double add: new=, prev=, next=. kernel BUG at lib/list_debug.c:35! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI Workqueue: vsock-loopback vsock_loopback_work RIP: 0010:__list_add_valid_or_report+0x11f/0x130 Call Trace: vsock_insert_connected.cold+0xe/0x13 virtio_transport_recv_pkt+0x10e9/0x1460 vsock_loopback_work+0x305/0x480 process_one_work+0xe4c/0x1560 worker_thread+0x4f1/0xd60 kthread+0x36e/0x470 ret_from_fork+0x47b/0x6b0 ret_from_fork_asm+0x1a/0x30 This fix is supplementary to commit 002541ef650b ("vsock: Ignore signal/timeout on connect() if already established"). Details under Link.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-10-28 11:17:42.770000
Last modified
2026-10-28 11:17:42.770000
View original CVE JSON
{
  "id": "CVE-2026-99213",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-28T11:17:42.770",
  "lastModified": "2026-10-28T11:17:42.770",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock: treat TCP_CLOSING as once-established\n\nHandle the TCP_ESTABLISHED -> TCP_CLOSING transition on OP_RST, which can\nrace with the connect loop. Immediately break and return 0 on\nESTABLISHED/CLOSING. The return value of connect() should reflect what\nhappened up to the point the connection was established or failed. Events\nthat occur afterwards must not affect it. E.g. even if OP_RW has already\nset sk_err, connect() should still return 0, not ENOBUFS because of it.\nAdapt the inaccurate comment above signal_pending().\n\nResetting a socket that is still present in connected_table can lead to\nmemory corruption. The reporter noted lost transports for in-flight skbs,\nand I have reproduced crashes caused by re-insertion into connected_table.\n\n  list_add double add: new=, prev=, next=.\n  kernel BUG at lib/list_debug.c:35!\n  Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\n  Workqueue: vsock-loopback vsock_loopback_work\n  RIP: 0010:__list_add_valid_or_report+0x11f/0x130\n  Call Trace:\n   vsock_insert_connected.cold+0xe/0x13\n   virtio_transport_recv_pkt+0x10e9/0x1460\n   vsock_loopback_work+0x305/0x480\n   process_one_work+0xe4c/0x1560\n   worker_thread+0x4f1/0xd60\n   kthread+0x36e/0x470\n   ret_from_fork+0x47b/0x6b0\n   ret_from_fork_asm+0x1a/0x30\n\nThis fix is supplementary to commit 002541ef650b (\"vsock: Ignore\nsignal/timeout on connect() if already established\"). Details under Link."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/vmw_vsock/af_vsock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "d021c344051af91f42c5ba9fdedc176740cbd238",
              "lessThan": "c2c5359ef2c33684fa3f3652fd761a483db8d1e7",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d021c344051af91f42c5ba9fdedc176740cbd238",
              "lessThan": "44d1ca05d6094a5d75c671a0545249186d790b8d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d021c344051af91f42c5ba9fdedc176740cbd238",
              "lessThan": "4f6ac74fa594a918d41255c941256e1d51592d3b",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/vmw_vsock/af_vsock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.9",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.9",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.59",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.13",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/44d1ca05d6094a5d75c671a0545249186d790b8d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4f6ac74fa594a918d41255c941256e1d51592d3b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c2c5359ef2c33684fa3f3652fd761a483db8d1e7",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}