CVE-2026-43249

HIGH EPSS 15.2%
Published May 6, 20261mo ago · Modified Jun 17, 20262w ago
8.8 CVSS 3.1
High
Find Similar
Published May 6, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

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 <48> 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] <TASK> [ 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] </TASK> [ 27.052465] Modules linked in: [ 27.052471] ---[ end trace 0000000000000000 ]---

CVSS Details

Base Score
8.8
Exploitability
2.8
Impact
5.9
Vector string
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Adjacent
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
15.2% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-415

Affected Products 3

VendorProductVersionRange
linuxlinux_kernel*≥4.14.308  –  <6.12.75
linuxlinux_kernel*≥6.13  –  <6.18.16
linuxlinux_kernel*≥6.19  –  <6.19.6

References 4

  • git.kernel.org https://git.kernel.org/stable/c/59e7707492576bdbfa8c1dbe7d90791df31e4773
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a5d00dff97118a32fcf5fec7a4c3f864c4620c4e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bf841d43f7a33d75675ba7f4e214ac1c67913065
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ce8ded2e61f47747e31eeefb44dc24a2160a7e32
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/59e7707492576bdbfa8c1dbe7d90791df31e4773
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a5d00dff97118a32fcf5fec7a4c3f864c4620c4e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bf841d43f7a33d75675ba7f4e214ac1c67913065
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ce8ded2e61f47747e31eeefb44dc24a2160a7e32
    Patch