« Back to list

CVE-2024-26689

Status: ModifiedHigh (7.8)—

In the Linux kernel, the following vulnerability has been resolved:

ceph: prevent use-after-free in encode_cap_msg()

In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed.

In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it.

encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob.

Read full descriptionShow less

This is the spot where the refcount must be increased to prevent "use after free" error.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (2)

Debian — Debian LinuxLinux — Linux Kernel

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2024-26689",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2024-26689",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-08-15T19:26:55.316031Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.8,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 2.8
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.8,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "8180d0c27b93a6eb60da1b08ea079e3926328214",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "70e329b440762390258a6fe8c0de93c9fdd56c77",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "f3f98d7d84b31828004545e29fd7262b9f444139",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "ae20db45e482303a20e56f2db667a9d9c54ac7e7",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "9030aaf9bf0a1eee47a154c316c789e959638b0f",
              "lessThan": "cda4672da1c26835dcbd7aec2bfed954eda9b5ef",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/ceph/caps.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.34"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "2.6.34",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "5.10.210",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "status": "unaffected",
              "version": "5.15.149",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "status": "unaffected",
              "version": "6.1.79",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "status": "unaffected",
              "version": "6.6.18",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "status": "unaffected",
              "version": "6.7.6",
              "versionType": "semver",
              "lessThanOrEqual": "6.7.*"
            },
            {
              "status": "unaffected",
              "version": "6.8",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/ceph/caps.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2024-04-03T15:15:52.427",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/70e329b440762390258a6fe8c0de93c9fdd56c77",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/8180d0c27b93a6eb60da1b08ea079e3926328214",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ae20db45e482303a20e56f2db667a9d9c54ac7e7",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cda4672da1c26835dcbd7aec2bfed954eda9b5ef",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f3f98d7d84b31828004545e29fd7262b9f444139",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/70e329b440762390258a6fe8c0de93c9fdd56c77",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/8180d0c27b93a6eb60da1b08ea079e3926328214",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/ae20db45e482303a20e56f2db667a9d9c54ac7e7",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/cda4672da1c26835dcbd7aec2bfed954eda9b5ef",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://git.kernel.org/stable/c/f3f98d7d84b31828004545e29fd7262b9f444139",
      "tags": [
        "Patch"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html",
      "tags": [
        "Mailing List"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: prevent use-after-free in encode_cap_msg()\n\nIn fs/ceph/caps.c, in encode_cap_msg(), \"use after free\" error was\ncaught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This\nimplies before the refcount could be increment here, it was freed.\n\nIn same file, in \"handle_cap_grant()\" refcount is decremented by this\nline - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race\noccurred and resource was freed by the latter line before the former\nline could increment it.\n\nencode_cap_msg() is called by __send_cap() and __send_cap() is called by\nceph_check_caps() after calling __prep_cap(). __prep_cap() is where\narg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where\nthe refcount must be increased to prevent \"use after free\" error."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ceph: evita el use-after-free en encode_cap_msg() En fs/ceph/caps.c, en encode_cap_msg(), KASAN detectó el error \"use after free\" en este línea - 'ceph_buffer_get(arg->xattr_buf);'. Esto implica que antes de que el recuento pudiera incrementarse aquí, fue liberado. En el mismo archivo, en \"handle_cap_grant()\", el refcount se reduce en esta línea: 'ceph_buffer_put(ci->i_xattrs.blob);'. Parece que se produjo una ejecución y la última línea liberó el recurso antes de que la primera línea pudiera incrementarlo. __send_cap() llama a encode_cap_msg() y ceph_check_caps() llama a __send_cap() después de llamar a __prep_cap(). __prep_cap() es donde arg->xattr_buf se asigna a ci->i_xattrs.blob. Este es el punto donde se debe aumentar el recuento para evitar el error \"use after free\"."
    }
  ],
  "lastModified": "2026-08-04T11:16:56.117",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "24443040-F8E0-445D-8395-40A94214526C",
              "versionEndExcluding": "5.10.210"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "0D0465BB-4053-4E15-9137-6696EBAE90FD",
              "versionEndExcluding": "5.15.149",
              "versionStartIncluding": "5.11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "656E2F29-1779-4EFC-AA64-8F984E2885B1",
              "versionEndExcluding": "6.1.79",
              "versionStartIncluding": "5.16"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "BD961E49-FEDA-47CF-BF23-4D2BD942B4E0",
              "versionEndExcluding": "6.6.18",
              "versionStartIncluding": "6.2"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "C6D6A5C8-7308-42A9-8A72-ABF3DEA4BB82",
              "versionEndExcluding": "6.7.6",
              "versionStartIncluding": "6.7"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B9F4EA73-0894-400F-A490-3A397AB7A517"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "056BD938-0A27-4569-B391-30578B309EE3"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F02056A5-B362-4370-9FF8-6F0BD384D520"
            }
          ],
          "operator": "OR"
        }
      ]
    },
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "07B237A9-69A3-4A9C-9DA0-4E06BD37AE73"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}