{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "e8f5f849ffce24490eb9449e98312b66c0dba76f"
            },
            {
              "fixed": "9ec991e148368e3207e98134c509a625097f7693"
            },
            {
              "fixed": "dd03fd658ea59821505e0e643b6b7cbdf51c4e1d"
            },
            {
              "fixed": "1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd"
            },
            {
              "fixed": "23b26f4408ac3f35a482d2e5cf6fc865d4201b71"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "b99f490ea87ebcca3a429fd8837067feb56a4c7c"
            },
            {
              "last_affected": "5ee28bcfbaacf289eb25c662a2862542ea6ce6a7"
            },
            {
              "last_affected": "6b67a6d2e50634fe127e656147c81915955e9f5e"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.15.128"
            },
            {
              "fixed": "5.16"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.1.47"
            },
            {
              "fixed": "6.2"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.4.12"
            },
            {
              "fixed": "6.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.5.0"
            },
            {
              "fixed": "6.12.111"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.53"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97556.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid leaking refcount when cifs_sb_tlink() fails\n\ncifs_oplock_break() takes over the reference that\ncifs_queue_oplock_break() acquired when it queued the work, and drops it\nwith _cifsFileInfo_put() once the break has been processed.\n\nOnly in setups with \"-o multiuser\", cifs_sb_tlink() may fail, at which\npoint cifs_oplock_break() returns without putting the file reference,\nmirroring the reference leak we already fixed in the companion patch to\ncifs_queue_oplock_break().\n\nThis would trigger a crash due to busy inodes on the next unmount:\n\n  BUG: Dentry ... still in use (1) [unmount of cifs cifs]\n  VFS: Busy inodes after unmount of cifs (cifs)\n\nDrop the reference on that path as well. Doing so before the out label\nmirrors the normal path, which also puts the reference before\ncifs_done_oplock_break().\n\nFound by Sashiko code review. The failure path was not exercised at\nruntime.",
  "id": "CVE-2026-97556",
  "modified": "2026-09-27T03:30:51.957236093Z",
  "published": "2026-09-25T10:21:47.078Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/23b26f4408ac3f35a482d2e5cf6fc865d4201b71"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9ec991e148368e3207e98134c509a625097f7693"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dd03fd658ea59821505e0e643b6b7cbdf51c4e1d"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97556.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-97556"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "smb: client: avoid leaking refcount when cifs_sb_tlink() fails"
}