- 5.5MediumCVSS base score
- 0.16%Exploitation in 30 daysEPSS · top 94% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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].
Timeline
ID reserved
By Linux
- 2 months later
· 2 months later
Published
- 11 months later
· 11 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.16% · top 94% of all CVEs (10 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-27869 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-38017)Record last updated .