Vulnerability-Lookup

FKIE_CVE-2023-53867

Vulnerability from fkie_nvd - Published: 2025-12-24 11:15 - Updated: 2026-08-04 10:19

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: ceph: fix potential use-after-free bug when trimming caps When trimming the caps and just after the 'session->s_cap_lock' is released in ceph_iterate_session_caps() the cap maybe removed by another thread, and when using the stale cap memory in the callbacks it will trigger use-after-free crash. We need to check the existence of the cap just after the 'ci->i_ceph_lock' being acquired. And do nothing if it's already removed.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/2b2515b8095cf2149bef44383a99d5b5677f1831
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/448875a73e16ba7d81dec9274ce9d33a12d092fb
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/aaf67de78807c59c35bafb5003d4fb457c764800
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ae6e935618d99cdba11eab4714092e7e5f13cf7e

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/ceph/caps.c",
            "fs/ceph/debugfs.c",
            "fs/ceph/mds_client.c",
            "fs/ceph/mds_client.h",
            "fs/ceph/super.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2b2515b8095cf2149bef44383a99d5b5677f1831",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "448875a73e16ba7d81dec9274ce9d33a12d092fb",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "ae6e935618d99cdba11eab4714092e7e5f13cf7e",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "aaf67de78807c59c35bafb5003d4fb457c764800",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ceph/caps.c",
            "fs/ceph/debugfs.c",
            "fs/ceph/mds_client.c",
            "fs/ceph/mds_client.h",
            "fs/ceph/super.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.34"
            },
            {
              "lessThan": "2.6.34",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.28",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.2.*",
              "status": "unaffected",
              "version": "6.2.15",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.3.*",
              "status": "unaffected",
              "version": "6.3.2",
              "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\nceph: fix potential use-after-free bug when trimming caps\n\nWhen trimming the caps and just after the \u0027session-\u003es_cap_lock\u0027 is\nreleased in ceph_iterate_session_caps() the cap maybe removed by\nanother thread, and when using the stale cap memory in the callbacks\nit will trigger use-after-free crash.\n\nWe need to check the existence of the cap just after the \u0027ci-\u003ei_ceph_lock\u0027\nbeing acquired. And do nothing if it\u0027s already removed."
    }
  ],
  "id": "CVE-2023-53867",
  "lastModified": "2026-08-04T10:19:24.590",
  "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": "2025-12-24T11:15:51.387",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/2b2515b8095cf2149bef44383a99d5b5677f1831"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/448875a73e16ba7d81dec9274ce9d33a12d092fb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/aaf67de78807c59c35bafb5003d4fb457c764800"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ae6e935618d99cdba11eab4714092e7e5f13cf7e"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Deferred"
}

CVE-2023-53867 (GCVE-0-2023-53867)

Vulnerability from cvelistv5 – Published: 2025-12-24 10:55 – Updated: 2026-08-05 09:16

Title

ceph: fix potential use-after-free bug when trimming caps

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/2b2515b8095cf2149…
https://git.kernel.org/stable/c/448875a73e16ba7d8…
https://git.kernel.org/stable/c/ae6e935618d99cdba…
https://git.kernel.org/stable/c/aaf67de78807c59c3…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 2f2dc053404febedc9c273452d9d518fb31fde72 , < 2b2515b8095cf2149bef44383a99d5b5677f1831 (git) Affected: 2f2dc053404febedc9c273452d9d518fb31fde72 , < 448875a73e16ba7d81dec9274ce9d33a12d092fb (git) Affected: 2f2dc053404febedc9c273452d9d518fb31fde72 , < ae6e935618d99cdba11eab4714092e7e5f13cf7e (git) Affected: 2f2dc053404febedc9c273452d9d518fb31fde72 , < aaf67de78807c59c35bafb5003d4fb457c764800 (git)
Linux	Linux	Affected: 2.6.34 Unaffected: 0 , < 2.6.34 (semver) Unaffected: 6.1.28 , ≤ 6.1.* (semver) Unaffected: 6.2.15 , ≤ 6.2.* (semver) Unaffected: 6.3.2 , ≤ 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": [
            "fs/ceph/caps.c",
            "fs/ceph/debugfs.c",
            "fs/ceph/mds_client.c",
            "fs/ceph/mds_client.h",
            "fs/ceph/super.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2b2515b8095cf2149bef44383a99d5b5677f1831",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "448875a73e16ba7d81dec9274ce9d33a12d092fb",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "ae6e935618d99cdba11eab4714092e7e5f13cf7e",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            },
            {
              "lessThan": "aaf67de78807c59c35bafb5003d4fb457c764800",
              "status": "affected",
              "version": "2f2dc053404febedc9c273452d9d518fb31fde72",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/ceph/caps.c",
            "fs/ceph/debugfs.c",
            "fs/ceph/mds_client.c",
            "fs/ceph/mds_client.h",
            "fs/ceph/super.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.34"
            },
            {
              "lessThan": "2.6.34",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.28",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.2.*",
              "status": "unaffected",
              "version": "6.2.15",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.3.*",
              "status": "unaffected",
              "version": "6.3.2",
              "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": "6.1.28",
                  "versionStartIncluding": "2.6.34",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.2.15",
                  "versionStartIncluding": "2.6.34",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.3.2",
                  "versionStartIncluding": "2.6.34",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.4",
                  "versionStartIncluding": "2.6.34",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix potential use-after-free bug when trimming caps\n\nWhen trimming the caps and just after the \u0027session-\u003es_cap_lock\u0027 is\nreleased in ceph_iterate_session_caps() the cap maybe removed by\nanother thread, and when using the stale cap memory in the callbacks\nit will trigger use-after-free crash.\n\nWe need to check the existence of the cap just after the \u0027ci-\u003ei_ceph_lock\u0027\nbeing acquired. And do nothing if it\u0027s already removed."
        }
      ],
      "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 - Every caller of the vulnerable `ceph_iterate_session_caps()` is driven by a message received from the remote Ceph MDS over TCP \u2014 `CEPH_SESSION_RECALL_STATE` (trim), `CLOSE`/`REJECT` (remove_session_caps), `STALE` (renewcaps) and MDS reconnect \u2014 processed in `handle_session()` on the messenger workqueue. A malicious, compromised, or on-path-spoofed MDS reaches the code purely with network traffic.\nAC:L - The attacker drives both sides of the race: `RECALL_STATE`/session-close/reconnect storms start the cap iteration while concurrent cap-revoke/export/session messages and the callback\u0027s own `d_prune_aliases()`/inode-eviction path remove caps. The window spans sleeping operations (`d_find_primary()`, `ceph_mdsc_build_path()`, dentry pruning) and can be retried indefinitely, so it is reliably hit.\nPR:N - No credentials or privileges on the victim client are required \u2014 the malicious MDS peer needs no local authority, and the code runs unauthenticated with respect to the client\u0027s privilege model. Locally, mere unprivileged access to a mounted CephFS is enough to generate the concurrent cap churn.\nUI:N - Exploitation needs no victim action beyond an already-mounted CephFS, which is the normal operating state of an affected system; the MDS drives the whole sequence on its own.\nS:U - The stale `struct ceph_cap` corruption and the resulting oops are confined to the kernel\u0027s own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The use-after-free gives a read primitive over freed/recycled `ceph_cap` slab memory, and `reconnect_caps_cb()` encodes those stale fields (`cap-\u003ecap_id`, `cap-\u003eissued`) directly into the reconnect message transmitted to the MDS, exfiltrating freed-object contents to the attacker.\nI:H - The callbacks write into the stale object \u2014 `cap-\u003eseq/issue_seq/mseq/cap_gen = 0` in `reconnect_caps_cb()` and `cap-\u003eissued = cap-\u003eimplemented = CEPH_CAP_PIN` in `wake_up_session_cb()` \u2014 corrupting a recycled `ceph_cap` (and thus another inode\u0027s capability/coherency state), a UAF write primitive usable for heap grooming toward control-flow hijack.\nA:H - The reported real-world outcome is a kernel NULL-pointer dereference oops in `__ceph_remove_cap()` from the trim-caps path (Ceph tracker #43272), and any use-after-free of the cap object crashes the client; the MDS can trigger it repeatedly."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T09:16:28.667Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2b2515b8095cf2149bef44383a99d5b5677f1831"
        },
        {
          "url": "https://git.kernel.org/stable/c/448875a73e16ba7d81dec9274ce9d33a12d092fb"
        },
        {
          "url": "https://git.kernel.org/stable/c/ae6e935618d99cdba11eab4714092e7e5f13cf7e"
        },
        {
          "url": "https://git.kernel.org/stable/c/aaf67de78807c59c35bafb5003d4fb457c764800"
        }
      ],
      "title": "ceph: fix potential use-after-free bug when trimming caps",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-53867",
    "datePublished": "2025-12-24T10:55:25.430Z",
    "dateReserved": "2025-12-09T01:27:17.829Z",
    "dateUpdated": "2026-08-05T09:16:28.667Z",
    "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.

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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FKIE_CVE-2023-53867

CVE-2023-53867 (GCVE-0-2023-53867)

Tags

Sightings

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