Vulnerability-Lookup

FKIE_CVE-2026-43091

Vulnerability from fkie_nvd - Published: 2026-05-06 10:16 - Updated: 2026-05-19 20:42

Severity ?

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

Summary

In the Linux kernel, the following vulnerability has been resolved: xfrm: Wait for RCU readers during policy netns exit xfrm_policy_fini() frees the policy_bydst hash tables after flushing the policy work items and deleting all policies, but it does not wait for concurrent RCU readers to leave their read-side critical sections first. The policy_bydst tables are published via rcu_assign_pointer() and are looked up through rcu_dereference_check(), so netns teardown must also wait for an RCU grace period before freeing the table memory. Fix this by adding synchronize_rcu() before freeing the policy hash tables.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F2AB5131-D1D3-4634-BAD0-DCDA846721A3",
              "versionEndExcluding": "6.6.136",
              "versionStartIncluding": "4.9",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7F0AE5B5-23AC-4DCC-B37A-51CA1DAE7BA8",
              "versionEndExcluding": "6.12.83",
              "versionStartIncluding": "6.7",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8126B8B8-6D0B-4443-86C1-672AEE893555",
              "versionEndExcluding": "6.18.24",
              "versionStartIncluding": "6.13",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB",
              "versionEndExcluding": "6.19.14",
              "versionStartIncluding": "6.19",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
              "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
              "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
              "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
              "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
              "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
              "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*",
              "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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",
  "lastModified": "2026-05-19T20:42:35.963",
  "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": "2026-05-06T10:16:22.433",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2026-43091 (GCVE-0-2026-43091)

Vulnerability from cvelistv5 – Published: 2026-05-06 07:40 – Updated: 2026-05-11 22:17

Title

xfrm: Wait for RCU readers during policy netns exit

Summary

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

References

5 references

URL	Tags
https://git.kernel.org/stable/c/b66920a3348c0f63b…
https://git.kernel.org/stable/c/438b1f668ad58f46c…
https://git.kernel.org/stable/c/3733fce2871c9bca9…
https://git.kernel.org/stable/c/33a3149dd81a1e2f5…
https://git.kernel.org/stable/c/069daad4f2ae9c5c1…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < b66920a3348c0f63ba18365248fa21fbf0b3a937 (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 438b1f668ad58f46ce699bb48e4698a7839e3f9e (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 3733fce2871c9bca9dd18a1a23b1432ea215a094 (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 33a3149dd81a1e2f52b80ee1e0fc380b39f3d028 (git) Affected: e1e551bc56302b80ff930c966f9985095fb1b70d , < 069daad4f2ae9c5c108131995529d5f02392c446 (git)
Linux	Linux	Affected: 4.9 Unaffected: 0 , < 4.9 (semver) Unaffected: 6.6.136 , ≤ 6.6.* (semver) Unaffected: 6.12.83 , ≤ 6.12.* (semver) Unaffected: 6.18.24 , ≤ 6.18.* (semver) Unaffected: 6.19.14 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_policy.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "b66920a3348c0f63ba18365248fa21fbf0b3a937",
              "status": "affected",
              "version": "e1e551bc56302b80ff930c966f9985095fb1b70d",
              "versionType": "git"
            },
            {
              "lessThan": "438b1f668ad58f46ce699bb48e4698a7839e3f9e",
              "status": "affected",
              "version": "e1e551bc56302b80ff930c966f9985095fb1b70d",
              "versionType": "git"
            },
            {
              "lessThan": "3733fce2871c9bca9dd18a1a23b1432ea215a094",
              "status": "affected",
              "version": "e1e551bc56302b80ff930c966f9985095fb1b70d",
              "versionType": "git"
            },
            {
              "lessThan": "33a3149dd81a1e2f52b80ee1e0fc380b39f3d028",
              "status": "affected",
              "version": "e1e551bc56302b80ff930c966f9985095fb1b70d",
              "versionType": "git"
            },
            {
              "lessThan": "069daad4f2ae9c5c108131995529d5f02392c446",
              "status": "affected",
              "version": "e1e551bc56302b80ff930c966f9985095fb1b70d",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_policy.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.9"
            },
            {
              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.136",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.83",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.136",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.83",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.24",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.14",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "4.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "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"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T22:17:33.354Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/b66920a3348c0f63ba18365248fa21fbf0b3a937"
        },
        {
          "url": "https://git.kernel.org/stable/c/438b1f668ad58f46ce699bb48e4698a7839e3f9e"
        },
        {
          "url": "https://git.kernel.org/stable/c/3733fce2871c9bca9dd18a1a23b1432ea215a094"
        },
        {
          "url": "https://git.kernel.org/stable/c/33a3149dd81a1e2f52b80ee1e0fc380b39f3d028"
        },
        {
          "url": "https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446"
        }
      ],
      "title": "xfrm: Wait for RCU readers during policy netns exit",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43091",
    "datePublished": "2026-05-06T07:40:23.955Z",
    "dateReserved": "2026-05-01T14:12:55.984Z",
    "dateUpdated": "2026-05-11T22:17:33.354Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-43091

CVE-2026-43091 (GCVE-0-2026-43091)

Tags

Sightings

Nomenclature