Vulnerability-Lookup

FKIE_CVE-2026-89700

Vulnerability from fkie_nvd - Published: 2026-09-11 20:19 - Updated: 2026-09-11 20:19

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: nfsd: validate sockaddr length per family in listener_set nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY attribute with no minimum length. A CAP_NET_ADMIN caller can send a 16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener, kernel_bind). nfsd_nl_listener_set_doit() also parsed and validated each listener entry inline in two separate loops, interleaved with mutating the running listener configuration. The validation was duplicated, used an open-coded "nla_len < sizeof(struct sockaddr)" check that was too short for AF_INET6, and handled a malformed entry inconsistently depending on which loop noticed it. Add an nfsd_nl_validate_listeners() helper that walks the entire list once and confirms each entry parses, carries both an address and a transport name, and is long enough for its address family (sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6) for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking nfsd_mutex or creating the serv, so a malformed request fails cleanly with no side effects. Since every entry is known valid by the time the two existing loops run, drop the redundant presence and per-family length checks from both, leaving only the nla_parse_nested() call needed to extract the data.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2aca70c18c5f5d06004122861fb151d5fcc57faf",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            },
            {
              "lessThan": "22d0e4752ca88fd84196d22ebeedc905e6540440",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            },
            {
              "lessThan": "bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "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\nnfsd: validate sockaddr length per family in listener_set\n\nnfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY\nattribute with no minimum length. A CAP_NET_ADMIN caller can send a\n16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte\nOOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,\nkernel_bind).\n\nnfsd_nl_listener_set_doit() also parsed and validated each listener\nentry inline in two separate loops, interleaved with mutating the\nrunning listener configuration. The validation was duplicated, used an\nopen-coded \"nla_len \u003c sizeof(struct sockaddr)\" check that was too short\nfor AF_INET6, and handled a malformed entry inconsistently depending on\nwhich loop noticed it.\n\nAdd an nfsd_nl_validate_listeners() helper that walks the entire list\nonce and confirms each entry parses, carries both an address and a\ntransport name, and is long enough for its address family\n(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)\nfor AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking\nnfsd_mutex or creating the serv, so a malformed request fails cleanly\nwith no side effects.\n\nSince every entry is known valid by the time the two existing loops\nrun, drop the redundant presence and per-family length checks from\nboth, leaving only the nla_parse_nested() call needed to extract the\ndata."
    }
  ],
  "id": "CVE-2026-89700",
  "lastModified": "2026-09-11T20:19:57.187",
  "metrics": {},
  "published": "2026-09-11T20:19:57.187",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-89700 (GCVE-0-2026-89700)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:46 – Updated: 2026-09-11 19:46

Title

nfsd: validate sockaddr length per family in listener_set

Summary

Severity

No CVSS data available.

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/2aca70c18c5f5d060…
https://git.kernel.org/stable/c/22d0e4752ca88fd84…
https://git.kernel.org/stable/c/bdcc85c2b05a9378d…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 16a471177496c8e04a9793812c187a2c1a2192fa , < 2aca70c18c5f5d06004122861fb151d5fcc57faf (git) Affected: 16a471177496c8e04a9793812c187a2c1a2192fa , < 22d0e4752ca88fd84196d22ebeedc905e6540440 (git) Affected: 16a471177496c8e04a9793812c187a2c1a2192fa , < bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464 (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (semver) Unaffected: 6.18.50 , ≤ 6.18.* (semver) Unaffected: 7.2.4 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2aca70c18c5f5d06004122861fb151d5fcc57faf",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            },
            {
              "lessThan": "22d0e4752ca88fd84196d22ebeedc905e6540440",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            },
            {
              "lessThan": "bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464",
              "status": "affected",
              "version": "16a471177496c8e04a9793812c187a2c1a2192fa",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/nfsd/nfsctl.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: validate sockaddr length per family in listener_set\n\nnfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY\nattribute with no minimum length. A CAP_NET_ADMIN caller can send a\n16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte\nOOB read across three consumers (rpc_cmp_addr_port, svc_find_listener,\nkernel_bind).\n\nnfsd_nl_listener_set_doit() also parsed and validated each listener\nentry inline in two separate loops, interleaved with mutating the\nrunning listener configuration. The validation was duplicated, used an\nopen-coded \"nla_len \u003c sizeof(struct sockaddr)\" check that was too short\nfor AF_INET6, and handled a malformed entry inconsistently depending on\nwhich loop noticed it.\n\nAdd an nfsd_nl_validate_listeners() helper that walks the entire list\nonce and confirms each entry parses, carries both an address and a\ntransport name, and is long enough for its address family\n(sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6)\nfor AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking\nnfsd_mutex or creating the serv, so a malformed request fails cleanly\nwith no side effects.\n\nSince every entry is known valid by the time the two existing loops\nrun, drop the redundant presence and per-family length checks from\nboth, leaving only the nla_parse_nested() call needed to extract the\ndata."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-11T19:46:18.076Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf"
        },
        {
          "url": "https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440"
        },
        {
          "url": "https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464"
        }
      ],
      "title": "nfsd: validate sockaddr length per family in listener_set",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89700",
    "datePublished": "2026-09-11T19:46:18.076Z",
    "dateReserved": "2026-09-11T19:38:34.750Z",
    "dateUpdated": "2026-09-11T19:46:18.076Z",
    "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.
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