GHSA-j349-5p3c-r8v4 · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: comedi: Fix use of...
In the Linux kernel, the following vulnerability has been resolved: comedi: Fix use of uninitialized memory in do_insn_ioctl() and do_insnlist_ioctl() syzbot reports a KMSAN kernel-infoleak in `do_insn_ioctl()`. A kernel buffer is allocated to hold `insn->n` samples (each of which is an `unsigned int`). For some instruction types, `insn->n` samples are copied back to user-space, unless an error code is being returned. The problem is that not all the instruction handlers that need to return data to userspace fill in the whole `insn->n` samples, so that there is an information leak. There is a similar syzbot report for `do_insnlist_ioctl()`, although it does not have a reproducer for it at the time of writing. One culprit is `insn_rw_emulate_bits()` which is used as the handler for `INSN_READ` or `INSN_WRITE` instructions for subdevices that do not have a specific handler for that instruction, but do have an `INSN_BITS` handler. For `INSN_READ` it only fills in at most 1 sample, so if `insn->n` is greater than 1, the remaining `insn->n - 1` samples copied to userspace will be uninitialized kernel data. Another culprit is `vm80xx_ai_insn_read()` in the "vm80xx" driver. It never returns an error, even if it fails to fill the buffer. Fix it in `do_insn_ioctl()` and `do_insnlist_ioctl()` by making sure that uninitialized parts of the allocated buffer are zeroed before handling each instruction. Thanks to Arnaud Lecomte for their fix to `do_insn_ioctl()`. That fix replaced the call to `kmalloc_array()` with `kcalloc()`, but it is not always necessary to clear the whole buffer.
総合評価: CVE-2025-39684 は低リスク（24.2/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.16%、6 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% | 0.16% | +0.14% |
| 2 | 2025-09-06 | — | 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 |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
GHSA-j349-5p3c-r8v4 · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: comedi: Fix use of...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2025-39684 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-2025-39684 |
redhat
|
— | — | https://access.redhat.com/security/cve/CVE-2025-39684 |
suse
|
medium | CVE-2025-39684 severity moderate: SUSE including 448 source package names (2.1.3-6.80:kernel-default-base-6.4.0-35.1.21.12, 2.1.3-7.57:kernel-default-6.4.0-35.1, …), 871 product×package rows across 177 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (177 product lines)): Fixed 619, Known Affected 231, First Fixed 21. | https://www.suse.com/security/cve/CVE-2025-39684/ |
ubuntu
|
medium | CVE-2025-39684 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 180, released 150, needed 47, not-affected 17, needs-triage 2, pending 1. | https://ubuntu.com/security/CVE-2025-39684 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 2.6.29, < 5.15.190 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.16, < 6.1.149 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.2, < 6.6.103 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.7, < 6.12.44 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.13, < 6.16.4 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | 6.17 | cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:* |
| linux | linux_kernel | 6.17 | cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:* |
| debian | debian_linux | 11.0 | cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* |