Vulnerability-Lookup

FKIE_CVE-2023-54269

Vulnerability from fkie_nvd - Published: 2025-12-30 13:16 - Updated: 2026-08-04 11:16

Severity

9.8 (Critical) - CVSS:3.1/AV:N/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: SUNRPC: double free xprt_ctxt while still in use When an RPC request is deferred, the rq_xprt_ctxt pointer is moved out of the svc_rqst into the svc_deferred_req. When the deferred request is revisited, the pointer is copied into the new svc_rqst - and also remains in the svc_deferred_req. In the (rare?) case that the request is deferred a second time, the old svc_deferred_req is reused - it still has all the correct content. However in that case the rq_xprt_ctxt pointer is NOT cleared so that when xpo_release_xprt is called, the ctxt is freed (UDP) or possible added to a free list (RDMA). When the deferred request is revisited for a second time, it will reference this ctxt which may be invalid, and the free the object a second time which is likely to oops. So change svc_defer() to *always* clear rq_xprt_ctxt, and assert that the value is now stored in the svc_deferred_req.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7851771789e87108a92697194105ef0c9307dc5e
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e0c648627322a4c7e018e5c7f837c3c03e297dbb
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/fd86534872f445f54dc01e7db001e25eadf063a8

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/svc_xprt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7851771789e87108a92697194105ef0c9307dc5e",
              "status": "affected",
              "version": "f5e13d700a4d40ccde3d36e383f9247dcb3c1d2d",
              "versionType": "git"
            },
            {
              "lessThan": "fd86534872f445f54dc01e7db001e25eadf063a8",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "lessThan": "e0c648627322a4c7e018e5c7f837c3c03e297dbb",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "lessThan": "eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "11fab500f86403b2ebf6795feeade6e10302e448",
              "versionType": "git"
            },
            {
              "lessThan": "5.15.113",
              "status": "affected",
              "version": "5.15.35",
              "versionType": "semver"
            },
            {
              "lessThan": "5.18",
              "status": "affected",
              "version": "5.17.4",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/svc_xprt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "lessThan": "5.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.30",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.3.*",
              "status": "unaffected",
              "version": "6.3.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.4",
              "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\nSUNRPC: double free xprt_ctxt while still in use\n\nWhen an RPC request is deferred, the rq_xprt_ctxt pointer is moved out\nof the svc_rqst into the svc_deferred_req.\nWhen the deferred request is revisited, the pointer is copied into\nthe new svc_rqst - and also remains in the svc_deferred_req.\n\nIn the (rare?) case that the request is deferred a second time, the old\nsvc_deferred_req is reused - it still has all the correct content.\nHowever in that case the rq_xprt_ctxt pointer is NOT cleared so that\nwhen xpo_release_xprt is called, the ctxt is freed (UDP) or possible\nadded to a free list (RDMA).\nWhen the deferred request is revisited for a second time, it will\nreference this ctxt which may be invalid, and the free the object a\nsecond time which is likely to oops.\n\nSo change svc_defer() to *always* clear rq_xprt_ctxt, and assert that\nthe value is now stored in the svc_deferred_req."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nSUNRPC: doble liberaci\u00f3n de xprt_ctxt mientras a\u00fan est\u00e1 en uso\n\nCuando una solicitud RPC es diferida, el puntero rq_xprt_ctxt es movido fuera del svc_rqst hacia el svc_deferred_req.\nCuando la solicitud diferida es revisitada, el puntero es copiado en el nuevo svc_rqst - y tambi\u00e9n permanece en el svc_deferred_req.\n\nEn el caso (\u00bfraro?) de que la solicitud sea diferida por segunda vez, el antiguo svc_deferred_req es reutilizado - a\u00fan tiene todo el contenido correcto.\nSin embargo, en ese caso el puntero rq_xprt_ctxt NO es limpiado de modo que cuando se llama a xpo_release_xprt, el ctxt es liberado (UDP) o posiblemente a\u00f1adido a una lista de libres (RDMA).\nCuando la solicitud diferida es revisitada por segunda vez, har\u00e1 referencia a este ctxt el cual puede ser inv\u00e1lido, y liberar\u00e1 el objeto por segunda vez lo que probablemente causar\u00e1 un \u0027oops\u0027.\n\nAs\u00ed que cambie svc_defer() para *siempre* limpiar rq_xprt_ctxt, y afirme que el valor ahora est\u00e1 almacenado en el svc_deferred_req."
    }
  ],
  "id": "CVE-2023-54269",
  "lastModified": "2026-08-04T11:16:38.893",
  "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": "2025-12-30T13:16:15.737",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7851771789e87108a92697194105ef0c9307dc5e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e0c648627322a4c7e018e5c7f837c3c03e297dbb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fd86534872f445f54dc01e7db001e25eadf063a8"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Deferred"
}

CVE-2023-54269 (GCVE-0-2023-54269)

Vulnerability from cvelistv5 – Published: 2025-12-30 12:16 – Updated: 2026-08-05 09:18

Title

SUNRPC: double free xprt_ctxt while still in use

Summary

Severity

9.8 (Critical)


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

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/7851771789e87108a…
https://git.kernel.org/stable/c/fd86534872f445f54…
https://git.kernel.org/stable/c/e0c648627322a4c7e…
https://git.kernel.org/stable/c/eb8d3a2c809abd73a…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f5e13d700a4d40ccde3d36e383f9247dcb3c1d2d , < 7851771789e87108a92697194105ef0c9307dc5e (git) Affected: 773f91b2cf3f52df0d7508fdbf60f37567cdaee4 , < fd86534872f445f54dc01e7db001e25eadf063a8 (git) Affected: 773f91b2cf3f52df0d7508fdbf60f37567cdaee4 , < e0c648627322a4c7e018e5c7f837c3c03e297dbb (git) Affected: 773f91b2cf3f52df0d7508fdbf60f37567cdaee4 , < eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1 (git) Affected: 11fab500f86403b2ebf6795feeade6e10302e448 (git) Affected: 5.15.35 , < 5.15.113 (semver) Affected: 5.17.4 , < 5.18 (semver)
Linux	Linux	Affected: 5.18 Unaffected: 0 , < 5.18 (semver) Unaffected: 5.15.113 , ≤ 5.15.* (semver) Unaffected: 6.1.30 , ≤ 6.1.* (semver) Unaffected: 6.3.4 , ≤ 6.3.* (semver) Unaffected: 6.4 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/svc_xprt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7851771789e87108a92697194105ef0c9307dc5e",
              "status": "affected",
              "version": "f5e13d700a4d40ccde3d36e383f9247dcb3c1d2d",
              "versionType": "git"
            },
            {
              "lessThan": "fd86534872f445f54dc01e7db001e25eadf063a8",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "lessThan": "e0c648627322a4c7e018e5c7f837c3c03e297dbb",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "lessThan": "eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1",
              "status": "affected",
              "version": "773f91b2cf3f52df0d7508fdbf60f37567cdaee4",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "11fab500f86403b2ebf6795feeade6e10302e448",
              "versionType": "git"
            },
            {
              "lessThan": "5.15.113",
              "status": "affected",
              "version": "5.15.35",
              "versionType": "semver"
            },
            {
              "lessThan": "5.18",
              "status": "affected",
              "version": "5.17.4",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sunrpc/svc_xprt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "lessThan": "5.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.30",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.3.*",
              "status": "unaffected",
              "version": "6.3.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.4",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.113",
                  "versionStartIncluding": "5.15.35",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.30",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.3.4",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.4",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.17.4",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: double free xprt_ctxt while still in use\n\nWhen an RPC request is deferred, the rq_xprt_ctxt pointer is moved out\nof the svc_rqst into the svc_deferred_req.\nWhen the deferred request is revisited, the pointer is copied into\nthe new svc_rqst - and also remains in the svc_deferred_req.\n\nIn the (rare?) case that the request is deferred a second time, the old\nsvc_deferred_req is reused - it still has all the correct content.\nHowever in that case the rq_xprt_ctxt pointer is NOT cleared so that\nwhen xpo_release_xprt is called, the ctxt is freed (UDP) or possible\nadded to a free list (RDMA).\nWhen the deferred request is revisited for a second time, it will\nreference this ctxt which may be invalid, and the free the object a\nsecond time which is likely to oops.\n\nSo change svc_defer() to *always* clear rq_xprt_ctxt, and assert that\nthe value is now stored in the svc_deferred_req."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The vulnerable path is nfsd/sunrpc server-side request processing driven entirely by RPC datagrams received from remote clients over UDP port 2049 (or NFS/RDMA). No local access is needed; the attacker only sends network packets to the NFS server.\nAC:L - The attacker controls both deferral triggers \u2014 a novel (freely spoofable) UDP source address forces an ip_map cache miss, and an unresolved export/filehandle forces a second nfsd_fh/nfsd_export miss on the same request, which is exactly the first-contact sequence for a new client. Small datagrams stay linear so rq_xprt_ctxt is populated, making the trigger repeatable at will.\nPR:N - The deferrals occur inside svcauth_unix_set_client() and the export lookup, i.e. while the server is still deciding whether the client is permitted at all, so no credentials have been verified. AUTH_NULL/AUTH_UNIX requests from any host able to reach the nfsd port suffice.\nUI:N - nfsd threads process incoming RPCs and requeue deferred requests automatically with no action by any local user or administrator.\nS:U - The corruption is confined to kernel memory managed by the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed sk_buff is re-read and re-released (skb-\u003eusers, skb-\u003ehead, skb-\u003edestructor) and the double free returns the same slab object to two owners, giving type-confusion-based read primitives over adjacent kernel data. Per UAF guidance this is High.\nI:H - A double free of an sk_buff lets a remote attacker who reallocates the slot with sprayed packet data control fields such as skb-\u003edestructor and skb-\u003ehead, yielding arbitrary write / control-flow hijack; the RDMA variant double-adds a recv ctxt to the free list so two live receives share one DMA buffer.\nA:H - The commit itself notes the second free \"is likely to oops\"; a double free of an sk_buff or corruption of the RDMA recv ctxt free list panics the kernel and can be re-triggered repeatedly by an unauthenticated remote client."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:18:46.870Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7851771789e87108a92697194105ef0c9307dc5e"
        },
        {
          "url": "https://git.kernel.org/stable/c/fd86534872f445f54dc01e7db001e25eadf063a8"
        },
        {
          "url": "https://git.kernel.org/stable/c/e0c648627322a4c7e018e5c7f837c3c03e297dbb"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1"
        }
      ],
      "title": "SUNRPC: double free xprt_ctxt while still in use",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-54269",
    "datePublished": "2025-12-30T12:16:00.317Z",
    "dateReserved": "2025-12-30T12:06:44.518Z",
    "dateUpdated": "2026-08-05T09:18:46.870Z",
    "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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

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