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Full vulnerability report · 2025
CVE-2025-40163High confidence

sched/deadline: Stop dl_server before CPU goes offline

Linux · Linux

UnscoredAssess manually
Recommended action
Needs assessment

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

11 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinux-aws-6.17Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcp-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatency-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-6.17Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracle-6.17Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2025-124920

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionNeeds assessment

No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.

Patch available
01

What, why and how

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]

What

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]

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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]

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
the affected interface → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Unspecified
Privileges required
Not stated in the selected CVSS metric
User interaction
Not stated in the selected CVSS metric
Attack complexity
Not stated in the selected CVSS metric
Security boundary
Not stated in the selected CVSS metric
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
Not available from the selected scoring authority.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2025-2579Linux Kernel: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen im Linux-Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, die möglicherweise zu einer Denial-of-Service- Bedingung führen oder eine Speicherbeschädigung verursachen können.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-1064Multiples vulnérabilités dans le noyau Linux de SUSE

:23068-1 du 11 août 2026 https://www.suse.com/support/update/announcement/2026/suse-su-202623068-1 Référence CVE CVE-2023-2058 https://www.cve.org/CVERecord?id=CVE-2023-2058 Référence CVE CVE-2025-38238 https://www.cve.org/CVERecord?id=CVE-2025-38238 Référence CVE CVE-2025-38250 https://www.cve.org/CVERecord?id=CVE-2025-38250 Référence CVE CVE-2025-38469 https://www.cve.org/CVERecord?id=CVE-2025-38469 Référence CVE CVE-2025-38625 https://www.cve.org/CVERecord?id=CVE-2025-38625 Référence CVE CVE-2025-39964 https://www.cve.org/CVERecord?id=CVE-2025-39964 Référence CVE CVE-2025-40022 https://www.cve.org/CVERecord?id=CVE-2025-40022 Référence CVE CVE-2025-40163 https://www.cve.org/CVERecord?id=CVE-2025-40163 Référence CVE CVE-2025-40199 https://www.cve.org/CVERecord?id=CVE-2025-40199 Référence CVE CVE-2025-40216 https://www.cve.org/CVERecord?id=CVE-2025-40216 Référence CVE CVE-2025-54518 https://www.cve.org/CVERecord?id=CVE-2025-54518 Référence CVE CVE-2025-68179 https://www.cve.org/CVERecord?id=CVE-2025-68179 Référence CVE CVE-2025-68204 https://www.cve.org/CVERecord?id=CVE-2025-68204 Référence CVE CVE-2025-71273 https://www.cve.org/CVERecord?id=CVE-2025-71273 Référence CVE CVE-2025-71274 https://www.cve.org/CVERecord?id=CVE-2025-71274 Référence CVE CVE-2025-71286 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0227Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-40153 Référence CVE CVE-2025-40154 https://www.cve.org/CVERecord?id=CVE-2025-40154 Référence CVE CVE-2025-40155 https://www.cve.org/CVERecord?id=CVE-2025-40155 Référence CVE CVE-2025-40156 https://www.cve.org/CVERecord?id=CVE-2025-40156 Référence CVE CVE-2025-40158 https://www.cve.org/CVERecord?id=CVE-2025-40158 Référence CVE CVE-2025-40159 https://www.cve.org/CVERecord?id=CVE-2025-40159 Référence CVE CVE-2025-40160 https://www.cve.org/CVERecord?id=CVE-2025-40160 Référence CVE CVE-2025-40161 https://www.cve.org/CVERecord?id=CVE-2025-40161 Référence CVE CVE-2025-40162 https://www.cve.org/CVERecord?id=CVE-2025-40162 Référence CVE CVE-2025-40163 https://www.cve.org/CVERecord?id=CVE-2025-40163 Référence CVE CVE-2025-40164 https://www.cve.org/CVERecord?id=CVE-2025-40164 Référence CVE CVE-2025-40165 https://www.cve.org/CVERecord?id=CVE-2025-40165 Référence CVE CVE-2025-40166 https://www.cve.org/CVERecord?id=CVE-2025-40166 Référence CVE CVE-2025-40167 https://www.cve.org/CVERecord?id=CVE-2025-40167 Référence CVE CVE-2025-40168 https://www.cve.org/CVERecord?id=CVE-2025-40168 Référence CVE CVE-2025-40169 https://www.cve.org/CVERecord?id=CVE-2025-40169 Référence CVE CVE-2025-40170 https://www.cve.org/CVERecord?id=CVE-2025-40170 Référence CVE CVE-2025-40171 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0194Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-40153 Référence CVE CVE-2025-40154 https://www.cve.org/CVERecord?id=CVE-2025-40154 Référence CVE CVE-2025-40155 https://www.cve.org/CVERecord?id=CVE-2025-40155 Référence CVE CVE-2025-40156 https://www.cve.org/CVERecord?id=CVE-2025-40156 Référence CVE CVE-2025-40158 https://www.cve.org/CVERecord?id=CVE-2025-40158 Référence CVE CVE-2025-40159 https://www.cve.org/CVERecord?id=CVE-2025-40159 Référence CVE CVE-2025-40160 https://www.cve.org/CVERecord?id=CVE-2025-40160 Référence CVE CVE-2025-40161 https://www.cve.org/CVERecord?id=CVE-2025-40161 Référence CVE CVE-2025-40162 https://www.cve.org/CVERecord?id=CVE-2025-40162 Référence CVE CVE-2025-40163 https://www.cve.org/CVERecord?id=CVE-2025-40163 Référence CVE CVE-2025-40164 https://www.cve.org/CVERecord?id=CVE-2025-40164 Référence CVE CVE-2025-40165 https://www.cve.org/CVERecord?id=CVE-2025-40165 Référence CVE CVE-2025-40166 https://www.cve.org/CVERecord?id=CVE-2025-40166 Référence CVE CVE-2025-40167 https://www.cve.org/CVERecord?id=CVE-2025-40167 Référence CVE CVE-2025-40168 https://www.cve.org/CVERecord?id=CVE-2025-40168 Référence CVE CVE-2025-40169 https://www.cve.org/CVERecord?id=CVE-2025-40169 Référence CVE CVE-2025-40170 https://www.cve.org/CVERecord?id=CVE-2025-40170 Référence CVE CVE-2025-40171 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0169Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2025-40153 Référence CVE CVE-2025-40154 https://www.cve.org/CVERecord?id=CVE-2025-40154 Référence CVE CVE-2025-40155 https://www.cve.org/CVERecord?id=CVE-2025-40155 Référence CVE CVE-2025-40156 https://www.cve.org/CVERecord?id=CVE-2025-40156 Référence CVE CVE-2025-40158 https://www.cve.org/CVERecord?id=CVE-2025-40158 Référence CVE CVE-2025-40159 https://www.cve.org/CVERecord?id=CVE-2025-40159 Référence CVE CVE-2025-40160 https://www.cve.org/CVERecord?id=CVE-2025-40160 Référence CVE CVE-2025-40161 https://www.cve.org/CVERecord?id=CVE-2025-40161 Référence CVE CVE-2025-40162 https://www.cve.org/CVERecord?id=CVE-2025-40162 Référence CVE CVE-2025-40163 https://www.cve.org/CVERecord?id=CVE-2025-40163 Référence CVE CVE-2025-40164 https://www.cve.org/CVERecord?id=CVE-2025-40164 Référence CVE CVE-2025-40165 https://www.cve.org/CVERecord?id=CVE-2025-40165 Référence CVE CVE-2025-40166 https://www.cve.org/CVERecord?id=CVE-2025-40166 Référence CVE CVE-2025-40167 https://www.cve.org/CVERecord?id=CVE-2025-40167 Référence CVE CVE-2025-40168 https://www.cve.org/CVERecord?id=CVE-2025-40168 Référence CVE CVE-2025-40169 https://www.cve.org/CVERecord?id=CVE-2025-40169 Référence CVE CVE-2025-40170 https://www.cve.org/CVERecord?id=CVE-2025-40170 Référence CVE CVE-2025-40171 https://www.cve.org/CVERecord?id=

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
030167dcadf50a9f9dac4de6fa4c34f4f7afeed7 < d7fd56ed5e07e053a5eea6112d61fcaded653b87; 4ae8d9aa9f9dc7137ea5e564d79c5aa5af1bc45c < ab6c0f158508bb16d483add70b73a73f95651c33; 4ae8d9aa9f9dc7137ea5e564d79c5aa5af1bc45c < ee6e44dfe6e50b4a5df853d933a96bdff5309e6e; 6.17
Fixed
< 6.17; 6.17.5 ≤ 6.17.*; 6.18 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 12 Nov 2025 · Last source change 1 Jun 2026, 16:05 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceUnavailable
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2025-124920
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD not scheduled

Missing structured fields: CVSS base score, CWE classification. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2025-40163 · cve.blacktree.nl