Vulnerability-Lookup

CVE-2026-99054 (GCVE-0-2026-99054)

Vulnerability from cvelistv5 – Published: 2026-10-23 12:22 – Updated: 2026-10-24 14:10

Title

tipc: destroy topsrv workqueues before closing connections

Summary

In the Linux kernel, the following vulnerability has been resolved: tipc: destroy topsrv workqueues before closing connections tipc_topsrv_stop() closed subscriber connections while the topology server's send and receive workqueues were still running. Socket callbacks and subscription events could then queue more work, and in-flight send/recv work could drop the last connection reference during the conn_idr walk. That race produced several teardown failures: refcount_t addition on 0 from conn_get() on a connection whose release was blocked on idr_lock, a subsequent use-after-free in tipc_conn_close(), queue_work() on an already destroyed workqueue from the listener data-ready callback, and an RCU stall in tipc_topsrv_exit_net() while the walk spun under idr_lock. Clear srv->listener under idr_lock so it acts as a shutdown flag, skip queue_work() once it is NULL, destroy the workqueues to flush in-flight work, and only then close the remaining connections. Refuse tipc_conn_lookup() after that flag is cleared, and drop idr_lock when the teardown walk finds no connection, so an in-flight subscription event cannot pin idr_in_use while the walk holds the lock. v3 supersedes the narrower in-thread diff Tung Quang Nguyen posted on 2026-09-23. It keeps his teardown order and adds the lookup refusal and the empty-idr unlock.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7061 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/7f796bb3b440d7f1b…
https://git.kernel.org/stable/c/da9c16568bc79140a…
https://git.kernel.org/stable/c/0af8780bdfdfc91fb…
https://git.kernel.org/stable/c/fb717c536af2aafec…
https://git.kernel.org/stable/c/3acdd44385bc7e2e5…

Impacted products

2 products

Vendor	Product	Version	CPE status
Linux	Linux	Affected: c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f , < 7f796bb3b440d7f1b14c0e3b520462eb34f553af (git) Affected: c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f , < da9c16568bc79140a54c1f5fcf07a0305df47b37 (git) Affected: c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f , < 0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e (git) Affected: c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f , < fb717c536af2aafeca520ff11d1e0f25f7ab8fa9 (git) Affected: c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f , < 3acdd44385bc7e2e57605e073691ce69cc5a960d (git)	guessed
Linux	Linux	Affected: 3.11 Unaffected: 0 , < 3.11 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.113 , ≤ 6.12.* (semver) Unaffected: 6.18.57 , ≤ 6.18.* (semver) Unaffected: 7.2.11 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)	guessed

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/tipc/topsrv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7f796bb3b440d7f1b14c0e3b520462eb34f553af",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "da9c16568bc79140a54c1f5fcf07a0305df47b37",
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              "versionType": "git"
            },
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              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "fb717c536af2aafeca520ff11d1e0f25f7ab8fa9",
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              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "3acdd44385bc7e2e57605e073691ce69cc5a960d",
              "status": "affected",
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              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/tipc/topsrv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.11"
            },
            {
              "lessThan": "3.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "3.11",
                  "vulnerable": true
                },
                {
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                  "versionEndExcluding": "6.12.113",
                  "versionStartIncluding": "3.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.57",
                  "versionStartIncluding": "3.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.11",
                  "versionStartIncluding": "3.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "3.11",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: destroy topsrv workqueues before closing connections\n\ntipc_topsrv_stop() closed subscriber connections while the topology\nserver\u0027s send and receive workqueues were still running. Socket\ncallbacks and subscription events could then queue more work, and\nin-flight send/recv work could drop the last connection reference\nduring the conn_idr walk.\n\nThat race produced several teardown failures: refcount_t addition on\n0 from conn_get() on a connection whose release was blocked on\nidr_lock, a subsequent use-after-free in tipc_conn_close(),\nqueue_work() on an already destroyed workqueue from the listener\ndata-ready callback, and an RCU stall in tipc_topsrv_exit_net()\nwhile the walk spun under idr_lock.\n\nClear srv-\u003elistener under idr_lock so it acts as a shutdown flag,\nskip queue_work() once it is NULL, destroy the workqueues to flush\nin-flight work, and only then close the remaining connections.\nRefuse tipc_conn_lookup() after that flag is cleared, and drop\nidr_lock when the teardown walk finds no connection, so an\nin-flight subscription event cannot pin idr_in_use while the\nwalk holds the lock.\n\nv3 supersedes the narrower in-thread diff Tung Quang Nguyen\nposted on 2026-09-23. It keeps his teardown order and adds the\nlookup refusal and the empty-idr unlock."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - `unshare(CLONE_NEWUSER|CLONE_NEWNET)` creates the per-net TIPC server; local `socket(AF_TIPC)`, `connect(TIPC_TOP_SRV)`, and `send()` churn followed by exit drives `cleanup_net()` -\u003e `tipc_topsrv_exit_net()` -\u003e patched `tipc_topsrv_stop()`. No remote message can cause the required namespace teardown.\nAC:L - The attacker controls both sides of the race: worker threads repeatedly create and close topology subscriptions while their process exits the network namespace, racing `rwork`/`swork` and socket callbacks against `tipc_topsrv_stop()`. No victim or hardware state is required.\nPR:L - `tipc_sk_create()`, `tipc_connect()`, and `tipc_conn_rcv_sub()` have no capability or authentication gate; an ordinary user can obtain the `CAP_SYS_ADMIN` needed for `CLONE_NEWNET` inside a new user namespace. No init-namespace privilege is required.\nUI:N - The attacker creates the namespaces, opens and floods `TIPC_TOP_SRV` connections, closes them, and exits to start `cleanup_net()` without any victim action.\nS:U - The freed `tipc_conn` and workqueue objects belong to the host kernel, and exploitation of `tipc_topsrv_stop()` affects that same kernel authority without crossing a VM, IOMMU, or other security boundary.\nC:H - `tipc_conn_kref_release()` frees `con` while teardown retains its address; `tipc_conn_close()` then reads `con-\u003esock-\u003esk` and follows reclaimed subscription and socket pointers. Reclaiming this object permits attacker-controlled pointer dereferences usable as kernel-memory read primitives.\nI:H - After the free, `tipc_conn_close()` modifies reclaimed `con-\u003eflags`, writes through `sk-\u003esk_user_data`, processes reclaimed subscription lists, and calls `kernel_sock_shutdown()` through `con-\u003esock-\u003eops`. These provide memory-write and control-flow primitives.\nA:H - The reported race produced a page fault in `tipc_conn_close()`, `queue_work()` on a destroyed receive workqueue, and an RCU stall in `tipc_topsrv_exit_net()`; these paths can oops, panic, or wedge the system."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-24T14:10:14.659Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af"
        },
        {
          "url": "https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37"
        },
        {
          "url": "https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e"
        },
        {
          "url": "https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9"
        },
        {
          "url": "https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d"
        }
      ],
      "title": "tipc: destroy topsrv workqueues before closing connections",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-99054",
    "datePublished": "2026-10-23T12:22:36.886Z",
    "dateReserved": "2026-09-25T10:25:14.388Z",
    "dateUpdated": "2026-10-24T14:10:14.659Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-99054",
      "date": "2026-10-24",
      "epss": "0.00209",
      "percentile": "0.10489"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "net/tipc/topsrv.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "7f796bb3b440d7f1b14c0e3b520462eb34f553af",
                    "status": "affected",
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                    "versionType": "git"
                  },
                  {
                    "lessThan": "da9c16568bc79140a54c1f5fcf07a0305df47b37",
                    "status": "affected",
                    "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e",
                    "status": "affected",
                    "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "fb717c536af2aafeca520ff11d1e0f25f7ab8fa9",
                    "status": "affected",
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                    "versionType": "git"
                  },
                  {
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                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/tipc/topsrv.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "3.11"
                  },
                  {
                    "lessThan": "3.11",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.6.*",
                    "status": "unaffected",
                    "version": "6.6.160",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.113",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.57",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.11",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: destroy topsrv workqueues before closing connections\n\ntipc_topsrv_stop() closed subscriber connections while the topology\nserver\u0027s send and receive workqueues were still running. Socket\ncallbacks and subscription events could then queue more work, and\nin-flight send/recv work could drop the last connection reference\nduring the conn_idr walk.\n\nThat race produced several teardown failures: refcount_t addition on\n0 from conn_get() on a connection whose release was blocked on\nidr_lock, a subsequent use-after-free in tipc_conn_close(),\nqueue_work() on an already destroyed workqueue from the listener\ndata-ready callback, and an RCU stall in tipc_topsrv_exit_net()\nwhile the walk spun under idr_lock.\n\nClear srv-\u003elistener under idr_lock so it acts as a shutdown flag,\nskip queue_work() once it is NULL, destroy the workqueues to flush\nin-flight work, and only then close the remaining connections.\nRefuse tipc_conn_lookup() after that flag is cleared, and drop\nidr_lock when the teardown walk finds no connection, so an\nin-flight subscription event cannot pin idr_in_use while the\nwalk holds the lock.\n\nv3 supersedes the narrower in-thread diff Tung Quang Nguyen\nposted on 2026-09-23. It keeps his teardown order and adds the\nlookup refusal and the empty-idr unlock."
          }
        ],
        "id": "CVE-2026-99054",
        "lastModified": "2026-10-24T14:16:54.053",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-10-23T13:17:29.013",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    }
  }
}

FKIE_CVE-2026-99054

Vulnerability from fkie_nvd - Published: 2026-10-23 13:17 - Updated: 2026-10-24 14:16

Severity

7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/tipc/topsrv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7f796bb3b440d7f1b14c0e3b520462eb34f553af",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "da9c16568bc79140a54c1f5fcf07a0305df47b37",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "fb717c536af2aafeca520ff11d1e0f25f7ab8fa9",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            },
            {
              "lessThan": "3acdd44385bc7e2e57605e073691ce69cc5a960d",
              "status": "affected",
              "version": "c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/tipc/topsrv.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.11"
            },
            {
              "lessThan": "3.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: destroy topsrv workqueues before closing connections\n\ntipc_topsrv_stop() closed subscriber connections while the topology\nserver\u0027s send and receive workqueues were still running. Socket\ncallbacks and subscription events could then queue more work, and\nin-flight send/recv work could drop the last connection reference\nduring the conn_idr walk.\n\nThat race produced several teardown failures: refcount_t addition on\n0 from conn_get() on a connection whose release was blocked on\nidr_lock, a subsequent use-after-free in tipc_conn_close(),\nqueue_work() on an already destroyed workqueue from the listener\ndata-ready callback, and an RCU stall in tipc_topsrv_exit_net()\nwhile the walk spun under idr_lock.\n\nClear srv-\u003elistener under idr_lock so it acts as a shutdown flag,\nskip queue_work() once it is NULL, destroy the workqueues to flush\nin-flight work, and only then close the remaining connections.\nRefuse tipc_conn_lookup() after that flag is cleared, and drop\nidr_lock when the teardown walk finds no connection, so an\nin-flight subscription event cannot pin idr_in_use while the\nwalk holds the lock.\n\nv3 supersedes the narrower in-thread diff Tung Quang Nguyen\nposted on 2026-09-23. It keeps his teardown order and adds the\nlookup refusal and the empty-idr unlock."
    }
  ],
  "id": "CVE-2026-99054",
  "lastModified": "2026-10-24T14:16:54.053",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-10-23T13:17:29.013",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

GHSA-QW7P-7WVC-P5Q5

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-24 15:32

Details

In the Linux kernel, the following vulnerability has been resolved:

tipc: destroy topsrv workqueues before closing connections

tipc_topsrv_stop() closed subscriber connections while the topology server's send and receive workqueues were still running. Socket callbacks and subscription events could then queue more work, and in-flight send/recv work could drop the last connection reference during the conn_idr walk.

That race produced several teardown failures: refcount_t addition on 0 from conn_get() on a connection whose release was blocked on idr_lock, a subsequent use-after-free in tipc_conn_close(), queue_work() on an already destroyed workqueue from the listener data-ready callback, and an RCU stall in tipc_topsrv_exit_net() while the walk spun under idr_lock.

Clear srv->listener under idr_lock so it acts as a shutdown flag, skip queue_work() once it is NULL, destroy the workqueues to flush in-flight work, and only then close the remaining connections. Refuse tipc_conn_lookup() after that flag is cleared, and drop idr_lock when the teardown walk finds no connection, so an in-flight subscription event cannot pin idr_in_use while the walk holds the lock.

v3 supersedes the narrower in-thread diff Tung Quang Nguyen posted on 2026-09-23. It keeps his teardown order and adds the lookup refusal and the empty-idr unlock.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

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To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-99054"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T13:17:29Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: destroy topsrv workqueues before closing connections\n\ntipc_topsrv_stop() closed subscriber connections while the topology\nserver\u0027s send and receive workqueues were still running. Socket\ncallbacks and subscription events could then queue more work, and\nin-flight send/recv work could drop the last connection reference\nduring the conn_idr walk.\n\nThat race produced several teardown failures: refcount_t addition on\n0 from conn_get() on a connection whose release was blocked on\nidr_lock, a subsequent use-after-free in tipc_conn_close(),\nqueue_work() on an already destroyed workqueue from the listener\ndata-ready callback, and an RCU stall in tipc_topsrv_exit_net()\nwhile the walk spun under idr_lock.\n\nClear srv-\u003elistener under idr_lock so it acts as a shutdown flag,\nskip queue_work() once it is NULL, destroy the workqueues to flush\nin-flight work, and only then close the remaining connections.\nRefuse tipc_conn_lookup() after that flag is cleared, and drop\nidr_lock when the teardown walk finds no connection, so an\nin-flight subscription event cannot pin idr_in_use while the\nwalk holds the lock.\n\nv3 supersedes the narrower in-thread diff Tung Quang Nguyen\nposted on 2026-09-23. It keeps his teardown order and adds the\nlookup refusal and the empty-idr unlock.",
  "id": "GHSA-qw7p-7wvc-p5q5",
  "modified": "2026-10-24T15:32:50Z",
  "published": "2026-10-23T15:31:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99054"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0af8780bdfdfc91fb9127bddb9c48fab67dc9d9e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3acdd44385bc7e2e57605e073691ce69cc5a960d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7f796bb3b440d7f1b14c0e3b520462eb34f553af"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/da9c16568bc79140a54c1f5fcf07a0305df47b37"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fb717c536af2aafeca520ff11d1e0f25f7ab8fa9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

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CVE-2026-99054 (GCVE-0-2026-99054)

FKIE_CVE-2026-99054

GHSA-QW7P-7WVC-P5Q5

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