Vulnerability-Lookup

GHSA-JRPH-46WX-R2G3

Vulnerability from github – Published: 2026-05-06 12:30 – Updated: 2026-05-08 15:31

Details

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.

Severity ?

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-43091"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-06T10:16:22Z",
    "severity": "HIGH"
  },
  "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": "GHSA-jrph-46wx-r2g3",
  "modified": "2026-05-08T15:31:15Z",
  "published": "2026-05-06T12:30:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43091"
    },
    {
      "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"
    }
  ],
  "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"
    }
  ]
}

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

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.

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)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_policy.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
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            },
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              "lessThan": "069daad4f2ae9c5c108131995529d5f02392c446",
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              "versionType": "git"
            }
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        },
        {
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          "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"
            },
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              "lessThan": "4.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
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              "versionType": "semver"
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              "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": [
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          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                },
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        }
      ],
      "metrics": [
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            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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        },
        {
          "url": "https://git.kernel.org/stable/c/069daad4f2ae9c5c108131995529d5f02392c446"
        }
      ],
      "title": "xfrm: Wait for RCU readers during policy netns exit",
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        "engine": "bippy-1.2.0"
      }
    }
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    "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

GHSA-JRPH-46WX-R2G3

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

Tags

Sightings

Nomenclature