CVE-2026-72469 (GCVE-0-2026-72469)
Vulnerability from cvelistv5
Published
2026-08-15 05:57
Modified
2026-08-17 05:44
Severity ?
8.8 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix ep kref imbalance on ADDR_CHANGE rpcrdma_cm_event_handler() falls through to the disconnected: label on RDMA_CM_EVENT_ADDR_CHANGE and calls rpcrdma_ep_put() with no matching get when the event arrives before RDMA_CM_EVENT_ESTABLISHED. The kref then underflows during connect teardown and rpcrdma_xprt_disconnect() operates on a freed ep. Reference counts across a normal connection lifecycle: rpcrdma_ep_create() kref_init ->1 rpcrdma_xprt_connect() ep_get ->2 (before post_recvs) RDMA_CM_EVENT_ESTABLISHED ep_get ->3 RDMA_CM_EVENT_DISCONNECTED ep_put ->2 rpcrdma_xprt_drain() ep_put ->1 rpcrdma_xprt_disconnect() tail ep_put ->0 (ep_destroy) The connect-time get in rpcrdma_xprt_connect(), taken just before rpcrdma_post_recvs() "while there are outstanding Receives," is balanced by rpcrdma_xprt_drain. ADDR_CHANGE before ESTABLISHED has no get to consume, so its put drops the count to 1 and the drain put then frees the ep while rpcrdma_xprt_disconnect() still holds a pointer to it. Fix by dispatching on the prior re_connect_status via xchg(): for prev == 0 (pre-ESTABLISHED) wake the connect waiter and return with no put; for prev == 1 call rpcrdma_force_disconnect() and return. The case-1 arm relies on the subsequent RDMA_CM_EVENT_DISCONNECTED event -- reliably delivered when rdma_disconnect() is called on a still-connected cm_id -- to balance the ESTABLISHED get; rpcrdma_xprt_drain() continues to balance only that connect-time get. Any other prior value means teardown is already in flight.
References
Impacted products
Vendor Product Version
Linux Linux Version: 2acc5cae292355f5f18ad377a2a966e7f03c8fec
Version: 2acc5cae292355f5f18ad377a2a966e7f03c8fec
Version: 2acc5cae292355f5f18ad377a2a966e7f03c8fec
Version: 2acc5cae292355f5f18ad377a2a966e7f03c8fec
Version: 2fcbf07a4f23174a45e015b62a8e42ddbc2e53ef
Version: 5.7.9   ≤
Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/xprtrdma/verbs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "cfd1bab66b042da7a778786685125656c695931b",
              "status": "affected",
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "versionType": "git"
            },
            {
              "lessThan": "d0479c2b12974aa188b10d221a5770126b118b6d",
              "status": "affected",
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "versionType": "git"
            },
            {
              "lessThan": "ffc07790539736a5d029f6a3c966b46c529f93a8",
              "status": "affected",
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "versionType": "git"
            },
            {
              "lessThan": "af9b65b29af341932625c4283dc7a23cdb62688a",
              "status": "affected",
              "version": "2acc5cae292355f5f18ad377a2a966e7f03c8fec",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "2fcbf07a4f23174a45e015b62a8e42ddbc2e53ef",
              "versionType": "git"
            },
            {
              "lessThan": "5.8",
              "status": "affected",
              "version": "5.7.9",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/xprtrdma/verbs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.8"
            },
            {
              "lessThan": "5.8",
              "status": "unaffected",
              "version": "0",
              "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"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "5.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "5.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "5.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "5.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.7.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxprtrdma: Fix ep kref imbalance on ADDR_CHANGE\n\nrpcrdma_cm_event_handler() falls through to the disconnected: label\non RDMA_CM_EVENT_ADDR_CHANGE and calls rpcrdma_ep_put() with no\nmatching get when the event arrives before RDMA_CM_EVENT_ESTABLISHED.\nThe kref then underflows during connect teardown and\nrpcrdma_xprt_disconnect() operates on a freed ep.\n\nReference counts across a normal connection lifecycle:\n\n    rpcrdma_ep_create()             kref_init     -\u003e1\n    rpcrdma_xprt_connect()          ep_get        -\u003e2  (before post_recvs)\n    RDMA_CM_EVENT_ESTABLISHED       ep_get        -\u003e3\n    RDMA_CM_EVENT_DISCONNECTED      ep_put        -\u003e2\n    rpcrdma_xprt_drain()            ep_put        -\u003e1\n    rpcrdma_xprt_disconnect() tail  ep_put        -\u003e0  (ep_destroy)\n\nThe connect-time get in rpcrdma_xprt_connect(), taken just before\nrpcrdma_post_recvs() \"while there are outstanding Receives,\" is\nbalanced by rpcrdma_xprt_drain. ADDR_CHANGE before ESTABLISHED has\nno get to consume, so its put drops the count to 1 and the drain\nput then frees the ep while rpcrdma_xprt_disconnect() still holds a\npointer to it.\n\nFix by dispatching on the prior re_connect_status via xchg(): for\nprev == 0 (pre-ESTABLISHED) wake the connect waiter and return with\nno put; for prev == 1 call rpcrdma_force_disconnect() and return.\nThe case-1 arm relies on the subsequent RDMA_CM_EVENT_DISCONNECTED\nevent -- reliably delivered when rdma_disconnect() is called on a\nstill-connected cm_id -- to balance the ESTABLISHED get;\nrpcrdma_xprt_drain() continues to balance only that connect-time\nget. Any other prior value means teardown is already in flight."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:A - The bug is in the NFS/RPC-over-RDMA client reached during RDMA CM connect/reconnect to a remote server; ADDR_CHANGE is delivered on bonded RoCE/IB netdev failover on the storage network segment, a plausible adjacent-network trigger in HPC and cloud NFS-over-RDMA deployments.\nAC:L - Once NFS-over-RDMA is in use, an attacker can reliably drive repeated reconnect attempts and time or induce bonding failover so ADDR_CHANGE arrives pre-ESTABLISHED; the resulting kref underflow and UAF are deterministic, not a probabilistic memory-layout race.\nPR:N - Exploitation requires no privileges on the victim host\u2014only that NFS-over-RDMA is configured and reconnects occur\u2014while an adjacent attacker or malicious storage peer can provoke link failover and connection churn without authenticating to the victim system.\nUI:N - No victim user interaction is required beyond normal automated NFS-over-RDMA client reconnect activity already performed by the kernel when links fail or sessions drop.\nS:U - Impact is kernel memory corruption and potential local privilege escalation within the same kernel security domain, not a cross-boundary escape such as VM guest-to-host or IOMMU bypass.\nC:H - Premature free of rpcrdma_ep leaves dangling pointers used in rpcrdma_xprt_disconnect (rdma_disconnect, ib_drain_rq/sq), a classic kernel heap UAF that can be leveraged for arbitrary memory disclosure via controlled reuse of the freed endpoint object.\nI:H - Teardown continues to operate on the freed endpoint and associated RDMA/IB state, enabling heap corruption and potential arbitrary kernel write or control-flow hijack, not merely a benign NULL dereference crash.\nA:H - The kref imbalance causes premature endpoint destruction during disconnect teardown, which can trigger kernel oops/panic from use-after-free even when exploitation for code execution is not attempted."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:44:33.996Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/cfd1bab66b042da7a778786685125656c695931b"
        },
        {
          "url": "https://git.kernel.org/stable/c/d0479c2b12974aa188b10d221a5770126b118b6d"
        },
        {
          "url": "https://git.kernel.org/stable/c/ffc07790539736a5d029f6a3c966b46c529f93a8"
        },
        {
          "url": "https://git.kernel.org/stable/c/af9b65b29af341932625c4283dc7a23cdb62688a"
        }
      ],
      "title": "xprtrdma: Fix ep kref imbalance on ADDR_CHANGE",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72469",
    "datePublished": "2026-08-15T05:57:11.829Z",
    "dateReserved": "2026-08-09T03:40:39.934Z",
    "dateUpdated": "2026-08-17T05:44:33.996Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.