GHSA-8pm8-q9qq-gqgp · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Clear Present...
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Clear Present bit before tearing down PASID entry The Intel VT-d Scalable Mode PASID table entry consists of 512 bits (64 bytes). When tearing down an entry, the current implementation zeros the entire 64-byte structure immediately using multiple 64-bit writes. Since the IOMMU hardware may fetch these 64 bytes using multiple internal transactions (e.g., four 128-bit bursts), updating or zeroing the entire entry while it is active (P=1) risks a "torn" read. If a hardware fetch occurs simultaneously with the CPU zeroing the entry, the hardware could observe an inconsistent state, leading to unpredictable behavior or spurious faults. Follow the "Guidance to Software for Invalidations" in the VT-d spec (Section 6.5.3.3) by implementing the recommended ownership handshake: 1. Clear only the 'Present' (P) bit of the PASID entry. 2. Use a dma_wmb() to ensure the cleared bit is visible to hardware before proceeding. 3. Execute the required invalidation sequence (PASID cache, IOTLB, and Device-TLB flush) to ensure the hardware has released all cached references. 4. Only after the flushes are complete, zero out the remaining fields of the PASID entry. Also, add a dma_wmb() in pasid_set_present() to ensure that all other fields of the PASID entry are visible to the hardware before the Present bit is set.
総合評価: CVE-2026-45894 は低リスク（32.7/100）。CVSS 深刻度は高。悪用される可能性が高い（EPSS 0.14%、4 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% | 0.14% | +0.13% |
| 2 | 2026-05-28 | — | 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 |
|
1.1 | 6.0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
GHSA-8pm8-q9qq-gqgp · 深刻度： high — In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Clear Present...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-45894 not yet assigned 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-2026-45894 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-45894 |
suse
|
high | — | https://www.suse.com/security/cve/CVE-2026-45894/ |
ubuntu
|
medium | CVE-2026-45894 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1422 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1024, ignored 169, needed 111, released 84, not-affected 33, needs-triage 1. | https://ubuntu.com/security/CVE-2026-45894 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 5.0, < 6.12.75 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.13, < 6.18.14 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.19, < 6.19.4 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |