Vulnerability in Kernel (CVE-2025-38017)

Summary

Vulnerability in Kernel (CVE-2025-38017). Risk of unauthorized operations or information disclosure. Exploitable via timed_out. Mitigation: upgrade to 6.14.8 or later.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

fs/eventpoll: fix endless busy loop after timeout has expired

After commit 0a65bc27bd64 ("eventpoll: Set epoll timeout if it's in
the future"), the following program would immediately enter a busy
loop in the kernel:

int main() {
  int e = epoll_create1(0);
  struct epoll_event event = {.events = EPOLLIN};
  epoll_ctl(e, EPOLL_CTL_ADD, 0, &event);
  const struct timespec timeout = {.tv_nsec = 1};
  epoll_pwait2(e, &event, 1, &timeout, 0);
}

This happens because the given (non-zero) timeout of 1 nanosecond
usually expires before ep_poll() is entered and then
ep_schedule_timeout() returns false, but timed_out is never set
because the code line that sets it is skipped. This quickly turns
into a soft lockup, RCU stalls and deadlocks, inflicting severe
headaches to the whole system.

When the timeout has expired, we don't need to schedule a hrtimer, but
we should set the timed_out variable. Therefore, I suggest moving
the ep_schedule_timeout() check into the timed_out expression
instead of skipping it.

brauner: Note that there was an earlier fix by Joe Damato in response to
my bug report in [1].

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2025-38017 has been found in Kernel.
Attackers can target a specific entry point like timed_out over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.14.8 or later.
If unsure, ask your IT team or search "Kernel CVE-2025-38017" on the vendor's site.

CVE-2025-38017 (Kernel)
Attack surface: timed_out
Patched: 6.14.8 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel. Attackers reach the vulnerable code path via timed_out.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel. Attack surface: timed_out.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 6.14.8.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 6.14.8
```
ステージング環境で 6.14.8 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"6.14.4"},{"fixed":"6.14.8"}]}]