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FKIE_CVE-2026-74398

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:19
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD addrconf_dad_failure() transitions ifp->state from DAD to POSTDAD via addrconf_dad_end(), which drops ifp->lock on return. The lock is re-acquired after net_info_ratelimited(). A concurrent ipv6_del_addr() can take the lock in that window, set ifp->state to DEAD and run list_del_rcu(&ifp->if_list). addrconf_dad_failure() then overwrites DEAD with ERRDAD at errdad: and schedules a new dad_work. The work calls ipv6_del_addr() again, hitting the already-poisoned list entry: general protection fault: 0000 [#1] SMP NOPTI CPU: 4 PID: 217 Comm: kworker/4:1 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:ipv6_del_addr+0xe9/0x280 RAX: dead000000000122 Call Trace: addrconf_dad_stop+0x113/0x140 addrconf_dad_work+0x28c/0x430 process_one_work+0x1eb/0x3b0 worker_thread+0x4d/0x400 kthread+0x104/0x140 ret_from_fork+0x35/0x40 Fold the addrconf_dad_end() logic into addrconf_dad_failure() under a single ifp->lock critical section. The STABLE_PRIVACY branch temporarily drops ifp->lock around address regeneration, so at lock_errdad: verify the state is still POSTDAD before transitioning to ERRDAD; bail out otherwise to avoid overwriting a state set by another path while the lock was released.
Impacted products
Vendor Product Version

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv6/addrconf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "47b05836705b63dab93d9ac7c69a3a507375ef80",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "d21be7d051012c6b572fa4e3334443c250216f7b",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "875c284c0f98b042bb97abad460f63a24c977f88",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "8ed0ce9ea58d677d1bac92614ee5f60f8ea57363",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "b61af0268e3d1308c466bf0be5dced844eafc1ef",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "e889aa99ad3ed48bb0ddcff6475b17542532d18b",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "lessThan": "627ac78f2741e2ebd2225e2e953b6964a8a9182f",
              "status": "affected",
              "version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "835b474b8f70fa68d68abffad37378e92f661802",
              "versionType": "git"
            },
            {
              "lessThan": "3.11",
              "status": "affected",
              "version": "3.10.105",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv6/addrconf.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.14"
            },
            {
              "lessThan": "3.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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\nipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD\n\naddrconf_dad_failure() transitions ifp-\u003estate from DAD to POSTDAD\nvia addrconf_dad_end(), which drops ifp-\u003elock on return.  The lock\nis re-acquired after net_info_ratelimited().  A concurrent\nipv6_del_addr() can take the lock in that window, set ifp-\u003estate\nto DEAD and run list_del_rcu(\u0026ifp-\u003eif_list).\n\naddrconf_dad_failure() then overwrites DEAD with ERRDAD at errdad:\nand schedules a new dad_work.  The work calls ipv6_del_addr()\nagain, hitting the already-poisoned list entry:\n\n  general protection fault: 0000 [#1] SMP NOPTI\n  CPU: 4 PID: 217 Comm: kworker/4:1\n  Workqueue: ipv6_addrconf addrconf_dad_work\n  RIP: 0010:ipv6_del_addr+0xe9/0x280\n  RAX: dead000000000122\n  Call Trace:\n   addrconf_dad_stop+0x113/0x140\n   addrconf_dad_work+0x28c/0x430\n   process_one_work+0x1eb/0x3b0\n   worker_thread+0x4d/0x400\n   kthread+0x104/0x140\n   ret_from_fork+0x35/0x40\n\nFold the addrconf_dad_end() logic into addrconf_dad_failure() under\na single ifp-\u003elock critical section.  The STABLE_PRIVACY branch\ntemporarily drops ifp-\u003elock around address regeneration, so at\nlock_errdad: verify the state is still POSTDAD before transitioning\nto ERRDAD; bail out otherwise to avoid overwriting a state set by\nanother path while the lock was released."
    }
  ],
  "id": "CVE-2026-74398",
  "lastModified": "2026-08-17T06:19:34.937",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-15T06:22:41.790",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/47b05836705b63dab93d9ac7c69a3a507375ef80"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/627ac78f2741e2ebd2225e2e953b6964a8a9182f"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/875c284c0f98b042bb97abad460f63a24c977f88"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8ed0ce9ea58d677d1bac92614ee5f60f8ea57363"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/b61af0268e3d1308c466bf0be5dced844eafc1ef"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/d21be7d051012c6b572fa4e3334443c250216f7b"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e889aa99ad3ed48bb0ddcff6475b17542532d18b"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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