{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "27291e2165b6de70c476b7b675308113edd69a60"
            },
            {
              "fixed": "053f2068cf9b0654b651fed5ad7649d3deb982bf"
            },
            {
              "fixed": "6c996b12bbe4a6023076e8eee3cfaf2cc99db76c"
            },
            {
              "fixed": "d6280fc540d8f4653c9b54a78cb747e128070f5e"
            },
            {
              "fixed": "544a5a665019cef394ce8bda97fa7a2cab253781"
            },
            {
              "fixed": "9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63"
            },
            {
              "fixed": "b5acacfdb8966abff91836c1c5bd7da59d8a526e"
            },
            {
              "fixed": "e4d8b7f176b976474e0800ba71ee2dfa3ce263c9"
            },
            {
              "fixed": "e7f698b09d4a7c36b299acf680fc50fe868e2bcd"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.16.0"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.110"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.51"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89923.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: s390: Free guest debug data on vcpu destroy\n\nkvm_s390_clear_bp_data() is only called from\nkvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or\ndisables debugging. A vCPU that is destroyed while hardware breakpoints\nare still armed - the normal case when the VMM just exits or crashes -\nleaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM\nfrees the vCPU right after kvm_arch_vcpu_destroy().\n\nThat is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but\nit is unbounded over VM lifetimes. The allocations are\nGFP_KERNEL_ACCOUNT, so the charge also outlives the exiting process and\npins dying memcgs.\n\nFix by clearing the debug data on vCPU destruction. Calling it\nunconditionally is fine: struct kvm_vcpu is zero allocated, so for a vCPU\nthat never enabled debugging the counters are 0 and the pointers NULL.",
  "id": "CVE-2026-89923",
  "modified": "2026-09-18T03:30:44.493602076Z",
  "published": "2026-09-16T10:32:16.765Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/053f2068cf9b0654b651fed5ad7649d3deb982bf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/544a5a665019cef394ce8bda97fa7a2cab253781"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6c996b12bbe4a6023076e8eee3cfaf2cc99db76c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9a32c4c6a6c23b7f5bf765eb5b83ba7f64a8ec63"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b5acacfdb8966abff91836c1c5bd7da59d8a526e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d6280fc540d8f4653c9b54a78cb747e128070f5e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e4d8b7f176b976474e0800ba71ee2dfa3ce263c9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e7f698b09d4a7c36b299acf680fc50fe868e2bcd"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89923.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89923"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "KVM: s390: Free guest debug data on vcpu destroy"
}