GHSA-wwvq-j7g5-3qrf · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: ext4: fix use-after-free in...
In the Linux kernel, the following vulnerability has been resolved: ext4: fix use-after-free in update_super_work when racing with umount Commit b98535d09179 ("ext4: fix bug_on in start_this_handle during umount filesystem") moved ext4_unregister_sysfs() before flushing s_sb_upd_work to prevent new error work from being queued via /proc/fs/ext4/xx/mb_groups reads during unmount. However, this introduced a use-after-free because update_super_work calls ext4_notify_error_sysfs() -> sysfs_notify() which accesses the kobject's kernfs_node after it has been freed by kobject_del() in ext4_unregister_sysfs(): update_super_work ext4_put_super ----------------- -------------- ext4_unregister_sysfs(sb) kobject_del(&sbi->s_kobj) __kobject_del() sysfs_remove_dir() kobj->sd = NULL sysfs_put(sd) kernfs_put() // RCU free ext4_notify_error_sysfs(sbi) sysfs_notify(&sbi->s_kobj) kn = kobj->sd // stale pointer kernfs_get(kn) // UAF on freed kernfs_node ext4_journal_destroy() flush_work(&sbi->s_sb_upd_work) Instead of reordering the teardown sequence, fix this by making ext4_notify_error_sysfs() detect that sysfs has already been torn down by checking s_kobj.state_in_sysfs, and skipping the sysfs_notify() call in that case. A dedicated mutex (s_error_notify_mutex) serializes ext4_notify_error_sysfs() against kobject_del() in ext4_unregister_sysfs() to prevent TOCTOU races where the kobject could be deleted between the state_in_sysfs check and the sysfs_notify() call.
総合評価: CVE-2026-31446 は低リスク（32.3/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.13%、3 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% | 0.13% | +0.11% |
| 2 | 2026-04-23 | — | 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 |
|---|---|---|---|---|---|---|
| 7.8 | 3.1 | HIGH |
|
1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
GHSA-wwvq-j7g5-3qrf · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: ext4: fix use-after-free in...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-31446 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5, open 1. | https://security-tracker.debian.org/tracker/CVE-2026-31446 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-31446 |
suse
|
medium | CVE-2026-31446 severity moderate: SUSE including 16 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 58 product×package rows across 12 product lines (SUSE Linux Enterprise Live Patching 12 SP5, SUSE Linux Enterprise Micro 5.0, … (12 product lines)): Known Not Affected 58. | https://www.suse.com/security/cve/CVE-2026-31446/ |
ubuntu
|
medium | CVE-2026-31446 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 169, needed 88, released 83, not-affected 57, needs-triage 4. | https://ubuntu.com/security/CVE-2026-31446 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 5.10.114, < 5.11 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.15.38, < 5.15.203 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.17.6, < 5.18 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.18.1, < 6.1.168 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.2, < 6.6.131 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.7, < 6.12.80 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.13, < 6.18.21 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.19, < 6.19.11 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:-:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:rc4:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:rc5:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:rc6:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:rc7:*:*:*:*:*:* |
| linux | linux_kernel | 5.18 | cpe:2.3:o:linux:linux_kernel:5.18:rc9:*:*:*:*:*:* |
| 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:*:*:*:*:*:* |