GHSA-hhj3-j6pg-f7mv · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: x86/iopl: Cure TIF_IO_BITMAP...
In the Linux kernel, the following vulnerability has been resolved: x86/iopl: Cure TIF_IO_BITMAP inconsistencies io_bitmap_exit() is invoked from exit_thread() when a task exists or when a fork fails. In the latter case the exit_thread() cleans up resources which were allocated during fork(). io_bitmap_exit() invokes task_update_io_bitmap(), which in turn ends up in tss_update_io_bitmap(). tss_update_io_bitmap() operates on the current task. If current has TIF_IO_BITMAP set, but no bitmap installed, tss_update_io_bitmap() crashes with a NULL pointer dereference. There are two issues, which lead to that problem: 1) io_bitmap_exit() should not invoke task_update_io_bitmap() when the task, which is cleaned up, is not the current task. That's a clear indicator for a cleanup after a failed fork(). 2) A task should not have TIF_IO_BITMAP set and neither a bitmap installed nor IOPL emulation level 3 activated. This happens when a kernel thread is created in the context of a user space thread, which has TIF_IO_BITMAP set as the thread flags are copied and the IO bitmap pointer is cleared. Other than in the failed fork() case this has no impact because kernel threads including IO workers never return to user space and therefore never invoke tss_update_io_bitmap(). Cure this by adding the missing cleanups and checks: 1) Prevent io_bitmap_exit() to invoke task_update_io_bitmap() if the to be cleaned up task is not the current task. 2) Clear TIF_IO_BITMAP in copy_thread() unconditionally. For user space forks it is set later, when the IO bitmap is inherited in io_bitmap_share(). For paranoia sake, add a warning into tss_update_io_bitmap() to catch the case, when that code is invoked with inconsistent state.
総合評価: CVE-2025-38100 は低リスク（24.4/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.17%、7 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 | 0.10% | 0.17% | +0.07% |
| 2 | 2026-04-29 | 0.03% | 0.10% | +0.08% |
| 3 | 2025-12-17 | — | 0.03% | — |
EPSS の全履歴 （全 5 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 |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
GHSA-hhj3-j6pg-f7mv · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: x86/iopl: Cure TIF_IO_BITMAP...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2025-38100 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 6. | https://security-tracker.debian.org/tracker/CVE-2025-38100 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2025-38100 |
suse
|
medium | CVE-2025-38100 severity moderate: SUSE including 432 source package names (2.1.3-6.67:kernel-default-base-6.4.0-32.1.21.10, 2.1.3-7.44:kernel-default-6.4.0-32.1, …), 802 product×package rows across 167 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (167 product lines)): Fixed 476, Known Affected 231, Known Not Affected 95. | https://www.suse.com/security/cve/CVE-2025-38100/ |
ubuntu
|
medium | CVE-2025-38100 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, released 169, ignored 164, not-affected 67, needed 3, needs-triage 2, pending 1. | https://ubuntu.com/security/CVE-2025-38100 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 5.5, < 5.10.239 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.11, < 5.15.186 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.16, < 6.1.142 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.2, < 6.6.94 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.7, < 6.12.34 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.13, < 6.15.3 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| debian | debian_linux | 11.0 | cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* |