{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.85-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.19.6-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  9p/xen: protect xen_9pfs_front_free against concurrent calls  The xenwatch thread can race with other back-end change notifications and call xen_9pfs_front_free() twice, hitting the observed general protection fault due to a double-free. Guard the teardown path so only one caller can release the front-end state at a time, preventing the crash.  This is a fix for the following double-free:  [   27.052347] Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI [   27.052357] CPU: 0 UID: 0 PID: 32 Comm: xenwatch Not tainted 6.18.0-02087-g51ab33fc0a8b-dirty #60 PREEMPT(none) [   27.052363] RIP: e030:xen_9pfs_front_free+0x1d/0x150 [   27.052368] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 41 55 41 54 55 48 89 fd 48 c7 c7 48 d0 92 85 53 e8 cb cb 05 00 48 8b 45 08 48 8b 55 00 \u003c48\u003e 3b 28 0f 85 f9 28 35 fe 48 3b 6a 08 0f 85 ef 28 35 fe 48 89 42 [   27.052377] RSP: e02b:ffffc9004016fdd0 EFLAGS: 00010246 [   27.052381] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88800d66e400 RCX: 0000000000000000 [   27.052385] RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000000 RDI: 0000000000000000 [   27.052389] RBP: ffff88800a887040 R08: 0000000000000000 R09: 0000000000000000 [   27.052393] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888009e46b68 [   27.052397] R13: 0000000000000200 R14: 0000000000000000 R15: ffff88800a887040 [   27.052404] FS:  0000000000000000(0000) GS:ffff88808ca57000(0000) knlGS:0000000000000000 [   27.052408] CS:  e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [   27.052412] CR2: 00007f9714004360 CR3: 0000000004834000 CR4: 0000000000050660 [   27.052418] Call Trace: [   27.052420]  \u003cTASK\u003e [   27.052422]  xen_9pfs_front_changed+0x5d5/0x720 [   27.052426]  ? xenbus_otherend_changed+0x72/0x140 [   27.052430]  ? __pfx_xenwatch_thread+0x10/0x10 [   27.052434]  xenwatch_thread+0x94/0x1c0 [   27.052438]  ? __pfx_autoremove_wake_function+0x10/0x10 [   27.052442]  kthread+0xf8/0x240 [   27.052445]  ? __pfx_kthread+0x10/0x10 [   27.052449]  ? __pfx_kthread+0x10/0x10 [   27.052452]  ret_from_fork+0x16b/0x1a0 [   27.052456]  ? __pfx_kthread+0x10/0x10 [   27.052459]  ret_from_fork_asm+0x1a/0x30 [   27.052463]  \u003c/TASK\u003e [   27.052465] Modules linked in: [   27.052471] ---[ end trace 0000000000000000 ]---",
  "id": "DEBIAN-CVE-2026-43249",
  "modified": "2026-09-14T16:47:27.652251474Z",
  "published": "2026-05-06T12:16:45.493Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-43249"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-43249"
  ]
}