GHSA-2pc8-ghgj-6c2f · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: cxl/mbox: validate payload...
In the Linux kernel, the following vulnerability has been resolved: cxl/mbox: validate payload size before accessing contents in cxl_payload_from_user_allowed() cxl_payload_from_user_allowed() casts and dereferences the input payload without first verifying its size. When a raw mailbox command is sent with an undersized payload (ie: 1 byte for CXL_MBOX_OP_CLEAR_LOG, which expects a 16-byte UUID), uuid_equal() reads past the allocated buffer, triggering a KASAN splat: BUG: KASAN: slab-out-of-bounds in memcmp+0x176/0x1d0 lib/string.c:683 Read of size 8 at addr ffff88810130f5c0 by task syz.1.62/2258 CPU: 2 UID: 0 PID: 2258 Comm: syz.1.62 Not tainted 6.19.0-dirty #3 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xab/0xe0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xce/0x650 mm/kasan/report.c:482 kasan_report+0xce/0x100 mm/kasan/report.c:595 memcmp+0x176/0x1d0 lib/string.c:683 uuid_equal include/linux/uuid.h:73 [inline] cxl_payload_from_user_allowed drivers/cxl/core/mbox.c:345 [inline] cxl_mbox_cmd_ctor drivers/cxl/core/mbox.c:368 [inline] cxl_validate_cmd_from_user drivers/cxl/core/mbox.c:522 [inline] cxl_send_cmd+0x9c0/0xb50 drivers/cxl/core/mbox.c:643 __cxl_memdev_ioctl drivers/cxl/core/memdev.c:698 [inline] cxl_memdev_ioctl+0x14f/0x190 drivers/cxl/core/memdev.c:713 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xa8/0x330 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdaf331ba79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdaf1d77038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fdaf3585fa0 RCX: 00007fdaf331ba79 RDX: 00002000000001c0 RSI: 00000000c030ce02 RDI: 0000000000000003 RBP: 00007fdaf33749df R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdaf3586038 R14: 00007fdaf3585fa0 R15: 00007ffced2af768 </TASK> Add 'in_size' parameter to cxl_payload_from_user_allowed() and validate the payload is large enough.
総合評価: CVE-2026-23327 は低リスク（29.4/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.12%、2 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.02% | 0.12% | +0.11% |
| 2 | 2026-03-25 | — | 0.02% | — |
EPSS の全履歴 （全 2 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 7.1 | 3.1 | HIGH |
|
1.8 | 5.2 | [email protected] |
GHSA-2pc8-ghgj-6c2f · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: cxl/mbox: validate payload...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
unimportant | CVE-2026-23327 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. | https://security-tracker.debian.org/tracker/CVE-2026-23327 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-23327 |
suse
|
medium | CVE-2026-23327 severity moderate: SUSE including 19 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 137 product×package rows across 25 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (25 product lines)): Known Not Affected 137. | https://www.suse.com/security/cve/CVE-2026-23327/ |
ubuntu
|
medium | CVE-2026-23327 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1413 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1018, ignored 169, not-affected 89, released 83, needed 54. | https://ubuntu.com/security/CVE-2026-23327 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 5.19.1, < 6.19.7 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | 5.19 | cpe:2.3:o:linux:linux_kernel:5.19:-:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* |
| linux | linux_kernel | 7.0 | cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* |