{ "affected": [ { "ranges": [ { "events": [ { "introduced": "c15fe55d14b3b4ded5af2a3260877460a6ffb8ad" }, { "fixed": "a5d00dff97118a32fcf5fec7a4c3f864c4620c4e" }, { "fixed": "59e7707492576bdbfa8c1dbe7d90791df31e4773" }, { "fixed": "bf841d43f7a33d75675ba7f4e214ac1c67913065" }, { "fixed": "ce8ded2e61f47747e31eeefb44dc24a2160a7e32" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "0" }, { "last_affected": "be03c4fe72384366fd4077a70966bd3b8fc49013" }, { "last_affected": "1ab4de11232e83b875b071aa44d1155634ca8a1e" }, { "last_affected": "7cc9dbae8a5f73bd555130384ea256018d28f283" }, { "last_affected": "3e0359f151ac151abe3fa71040e450ed69cb824b" }, { "last_affected": "8d3fc907d060c4fb33203e616a395a22083b6566" }, { "last_affected": "4f0e9244770f5b75a16d8c0929063cd336926764" }, { "last_affected": "5f6a8974e9ef317fe63f88bab1f33070195dd147" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "4.14.308" }, { "fixed": "4.15" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "4.19.276" }, { "fixed": "4.20" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "5.4.235" }, { "fixed": "5.5" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "5.10.173" }, { "fixed": "5.11" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "5.15.100" }, { "fixed": "5.16" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "6.1.18" }, { "fixed": "6.2" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" }, { "events": [ { "introduced": "6.2.5" }, { "fixed": "6.3" } ], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "type": "GIT" } ] }, { "package": { "ecosystem": "Linux", "name": "Kernel" }, "ranges": [ { "events": [ { "introduced": "6.3.0" }, { "fixed": "6.12.75" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.13.0" }, { "fixed": "6.18.16" } ], "type": "ECOSYSTEM" }, { "events": [ { "introduced": "6.19.0" }, { "fixed": "6.19.6" } ], "type": "ECOSYSTEM" } ] } ], "database_specific": { "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43249.json" }, "details": "In the Linux kernel, the following vulnerability has been resolved:\n\n9p/xen: protect xen_9pfs_front_free against concurrent calls\n\nThe xenwatch thread can race with other back-end change notifications\nand call xen_9pfs_front_free() twice, hitting the observed general\nprotection fault due to a double-free. Guard the teardown path so only\none caller can release the front-end state at a time, preventing the\ncrash.\n\nThis is a fix for the following double-free:\n\n[ 27.052347] Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI\n[ 27.052357] CPU: 0 UID: 0 PID: 32 Comm: xenwatch Not tainted 6.18.0-02087-g51ab33fc0a8b-dirty #60 PREEMPT(none)\n[ 27.052363] RIP: e030:xen_9pfs_front_free+0x1d/0x150\n[ 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\n[ 27.052377] RSP: e02b:ffffc9004016fdd0 EFLAGS: 00010246\n[ 27.052381] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88800d66e400 RCX: 0000000000000000\n[ 27.052385] RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000000 RDI: 0000000000000000\n[ 27.052389] RBP: ffff88800a887040 R08: 0000000000000000 R09: 0000000000000000\n[ 27.052393] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888009e46b68\n[ 27.052397] R13: 0000000000000200 R14: 0000000000000000 R15: ffff88800a887040\n[ 27.052404] FS: 0000000000000000(0000) GS:ffff88808ca57000(0000) knlGS:0000000000000000\n[ 27.052408] CS: e030 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 27.052412] CR2: 00007f9714004360 CR3: 0000000004834000 CR4: 0000000000050660\n[ 27.052418] Call Trace:\n[ 27.052420] \u003cTASK\u003e\n[ 27.052422] xen_9pfs_front_changed+0x5d5/0x720\n[ 27.052426] ? xenbus_otherend_changed+0x72/0x140\n[ 27.052430] ? __pfx_xenwatch_thread+0x10/0x10\n[ 27.052434] xenwatch_thread+0x94/0x1c0\n[ 27.052438] ? __pfx_autoremove_wake_function+0x10/0x10\n[ 27.052442] kthread+0xf8/0x240\n[ 27.052445] ? __pfx_kthread+0x10/0x10\n[ 27.052449] ? __pfx_kthread+0x10/0x10\n[ 27.052452] ret_from_fork+0x16b/0x1a0\n[ 27.052456] ? __pfx_kthread+0x10/0x10\n[ 27.052459] ret_from_fork_asm+0x1a/0x30\n[ 27.052463] \u003c/TASK\u003e\n[ 27.052465] Modules linked in:\n[ 27.052471] ---[ end trace 0000000000000000 ]---", "id": "CVE-2026-43249", "modified": "2026-07-08T05:39:00.325795289Z", "published": "2026-05-06T11:28:40.290Z", "references": [ { "type": "WEB", "url": "https://git.kernel.org/stable/c/59e7707492576bdbfa8c1dbe7d90791df31e4773" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/a5d00dff97118a32fcf5fec7a4c3f864c4620c4e" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/bf841d43f7a33d75675ba7f4e214ac1c67913065" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/ce8ded2e61f47747e31eeefb44dc24a2160a7e32" }, { "type": "ADVISORY", "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43249.json" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43249" }, { "type": "PACKAGE", "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git" } ], "schema_version": "1.7.5", "severity": [ { "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "type": "CVSS_V3" } ], "summary": "9p/xen: protect xen_9pfs_front_free against concurrent calls" }