CVE-2025-40163: linux

CVSS: UnknownDeferred
AliasesUBUNTU-CVE-2025-40163
Published 12-11-2025Last modified 01-06-2026

Vulnerability summary

CVE-2025-40163 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.1% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.20%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 11 · Related 11

Timeline

  1. 12-11-2025
    PublishedVulnerability first disclosed.
  2. 01-06-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: sched/deadline: Stop dl_server before CPU goes offline IBM CI tool reported kernel warning[1] when running a CPU removal operation through drmgr[2]. i.e "drmgr -c cpu -r -q 1" WARNING: CPU: 0 PID: 0 at kernel/sched/cpudeadline.c:219 cpudl_set+0x58/0x170 NIP [c0000000002b6ed8] cpudl_set+0x58/0x170 LR [c0000000002b7cb8] dl_server_timer+0x168/0x2a0 Call Trace: [c000000002c2f8c0] init_stack+0x78c0/0x8000 (unreliable) [c0000000002b7cb8] dl_server_timer+0x168/0x2a0 [c00000000034df84] __hrtimer_run_queues+0x1a4/0x390 [c00000000034f624] hrtimer_interrupt+0x124/0x300 [c00000000002a230] timer_interrupt+0x140/0x320 Git bisects to: commit 4ae8d9aa9f9d ("sched/deadline: Fix dl_server getting stuck") This happens since: - dl_server hrtimer gets enqueued close to cpu offline, when kthread_park enqueues a fair task. - CPU goes offline and drmgr removes it from cpu_present_mask. - hrtimer fires and warning is hit. Fix it by stopping the dl_server before CPU is marked dead. [1]: https://lore.kernel.org/all/8218e149-7718-4432-9312-f97297c352b9@linux.ibm.com/ [2]: https://github.com/ibm-power-utilities/powerpc-utils/tree/next/src/drmgr [sshegde: wrote the changelog and tested it]

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.20%

Chance of exploitation in the next 30 days

Percentile

9%

Versus all other CVEs

30-day change

+0.01 pp

From 0.18% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.20%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu93 products
  • linux< 6.17.0-14.14
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 6.17.0-1007.7
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux1 product
  • linux≥ 030167dcadf50a9f9dac4de6fa4c34f4f7afeed7, < d7fd56ed5e07e053a5eea6112d61fcaded653b87 | ≥ 4ae8d9aa9f9dc7137ea5e564d79c5aa5af1bc45c, < ab6c0f158508bb16d483add70b73a73f95651c33 | ≥ 4ae8d9aa9f9dc7137ea5e564d79c5aa5af1bc45c, < ee6e44dfe6e50b4a5df853d933a96bdff5309e6e | 6.17

2 vendors · 94 products

References

10 links